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Published
, Published online: 25 March 2026,
doi: 10.37188/lam.2026.024
The demand for compact, high-performance optical components has driven the development of increasingly sophisticated and miniaturized optical elements, often requiring complex and costly fabrication methods. In this work, we propose a cost-effective and accessible methodology for the fabrication of lenses and free-form optics using a commercially available stereolithography (SLA) 3D printer. A systematic characterization of six transparent photopolymer resins was conducted in terms of their spectroscopic, optical, and morphological properties, i.e., surface and dimensional properties. The evaluation encompassed parameters such as transmittance, autofluorescence, refractive index, and surface roughness. A straightforward and robust printing and post-treatment protocol was developed, facilitating the fabrication of optical components with over 80% transmittance, minimal intrinsic fluorescence, and a surface quality that is compatible with demanding optical applications. The fabricated components demonstrated excellent dimensional fidelity to digital designs and high reproducibility. To demonstrate the versatility of this approach, aspherical, miniaturized, and free-form lenses were designed and integrated into three fluorescence sensing systems, including oil (strip based) and chlorine (microfluidic based) detection platforms, as well as a smartphone-based SARSCoV-2 biosensor. The integration of customized 3D-printed optics has been shown to improve signal collection and readout performance, thereby highlighting the potential of this approach for broad application by a wide range of user groups in rapid prototyping and use in miniaturized optical systems. This work represents a significant advancement in the field of additive manufacturing, particularly in relation to the development of functional photonic devices. Furthermore, it opens new prospects for sensor applications in biosensing, microfluidics, imaging, and integrated optics.
Published
, Published online: 09 October 2025,
doi: 10.37188/lam.2025.026
Quartz tuning forks have been recently employed as infrared photodetectors in tunable laser diode spectroscopy because of their high responsivities and fast response time. As for all sensitive elements employed for photodetection, the main drawback is the limited bandwidth of their absorption spectrum. For quartz crystals, the high absorptance for wavelengths above 5 µm guarantees excellent performance in the mid-infrared range, that cannot be easily extended in the visible/near-infrared range because of its transparency from 0.2 to 5 µm. In this work, we report on the development of a laser surface functionalization process to enhance the optical absorption of quartz crystals, named hereafter Black Quartz, in the 1-5 µm spectral range. Black Quartz consists of surface modification of quartz crystal by ultra-fast-pulsed-laser-processing to create localized matrices-like patterns of craters on top. The surface modification decreases the transmittance of quartz in the 1-5 µm range from > 95% down to < 10%, while the transmittance above 5 µm remains unchanged. The Black Quartz process was applied on two quartz-tuning-forks mounted in a tunable laser diode spectroscopy sensor for detecting two water vapor absorption features, one in the near infrared and the other one in the mid-infrared. A comparable responsivity was estimated in detecting both absorption features, confirming the extension of the operation in the near-infrared range. This works represents an important and promising step towards the realization of quartz-based photodetector with high and flat responsivity in the whole infrared spectral range.
Published
, Published online: 04 June 2025,
doi: 10.37188/lam.2025.040
This study proposes a novel heterodyne grating interferometer designed to meet the multi-dimensional atomic-level measurement demands of next-generation lithography systems and large-scale atomic-level manufacturing. By utilizing a dual-frequency laser source, the interferometer enables simultaneous three-degree-of-freedom (3-DOF) displacement measurements. Key innovations include a compact, zero dead-zone optical path architecture, which enhances measurement robustness by minimizing sensitivity to laser source instabilities and atmospheric refractive index fluctuations. In addition, we present a systematic crosstalk error analysis, coupled with a corresponding compensation algorithm, effectively reducing crosstalk-induced errors to below 5%. Experimental evaluation of the 90 × 90 × 40 mm3 prototype demonstrates outstanding performance metrics: sub-nanometer resolutions (0.25 nm for X/Y-axes, 0.3 nm for Z-axis), superior linearity coefficients (6.9 × 10−5, 8.1 × 10−5, 16.2 × 10−5 for X-, Y-, and Z-axes, respectively), high repeatability (0.8 nm@1000 nm for all axes), exceptional long-term stability (20 nm XY-plane drift, 60 nm Z-axis drift over 1000 s), and practical measurement ranges exceeding 10 mm in-plane and 2 mm axially. Comparative analysis with state-of-the-art sensors demonstrates significant advantages in measurement precision, system integration, and multi-axis capability. This advancement highlights excellent potential for applications in integrated circuit fabrication, atomic-scale manufacturing, and ultra-precision metrology for aerospace systems.
Published
, Published online: 17 January 2025,
doi: 10.37188/lam.2025.001
In this study, a ray tracing model based on the law of reflection in vector form was developed to obtain the design parameters of multipass cells (MPC) with dense spot patterns. Four MPCs with distinct patterns were obtained using an established mathematical model. An MPC with a four-concentric-circle pattern exhibited the longest optical path length (OPL) of approximately 38 m and an optimal ratio of optical path length to volume (RLV) of 13.8 cm-2. A light-induced thermoelastic spectroscopy (LITES)-based methane (CH4) sensor was constructed for the first time using the developed optimal MPC and Raman fiber amplifier (RFA). A novel trapezoidal-tip quartz tuning fork (QTF) was used as the detector to further improve the sensing performance. The CH4-LITES sensor exhibited an excellent linear response to optical power and CH4 concentration. The minimum detection limit (MDL) of the CH4-LITES sensor reached 322 ppb when the output optical power of the RFA was 350 mW. The Allan deviation of the system indicated that the MDL decreased to 59.5 ppb when the average time was increased to 100 s.
Accepted
, Accepted article preview online: 30 July 2026,
doi: 10.37188/lam.2026.127
[PDF](786)
Optical coherence elastography (OCE) is a non-invasive imaging technique for high-resolution assessment of both tissue elasticity and viscoelasticity. Mechanical characterization enhances biomedical imaging by providing functional insights into tissue health beyond structural information alone. Accurate viscoelastic characterization requires estimating shear wave speed (SWS) across multiple frequencies, as dispersion induces frequency-dependent variations in wave speed. In this paper, we introduce a single-shot multi-frequency reverberant OCE (MFR-OCE) approach to enable reliable viscoelastic characterization by simultaneously capturing shear wave dynamics across multiple frequencies. We present the theoretical framework, experimental setup, and validation of MFR-OCE through simulations and experiments on homogeneous gelatin phantoms and one with an inclusion, ex vivo porcine corneas, and ex vivo bovine liver. Simulation results demonstrate that MFR-OCE estimates SWS with errors below 4% compared to ground truth. Phantom experiments show that MFR-OCE and single-frequency OCE yield closely matching SWS estimates, with differences below 3%. Furthermore, frequency-dependent dispersion coefficients observed in both biological tissues and phantoms align with the theoretical viscoelastic power-law model. The gelatin phantoms exhibit a low viscoelastic behavior with a power-law exponent of 0.13, while porcine corneas demonstrate intermediate viscoelastic behavior, with a power-law exponent of 0.33. The bovine liver shows significant frequency dependence, with a power-law exponent of 0.51. These findings demonstrate that MFR-OCE enables comprehensive viscoelastic characterization and is envisioned to provide a foundation for future development of clinically oriented OCE systems.
Accepted
, Accepted article preview online: 17 July 2026,
doi: 10.37188/lam.2026.124
[PDF](866)
Advancements in quantum-computing technologies require the scalable development of reliable qubit platforms. One promising strategy to address this challenge involves adapting the current silicon nanoelectronic technology to meet the requirements for semiconductor-based qubits. In this context, Si nanowires (NWs) are particularly attractive for realising spin-based qubits on fully depleted silicon on insulator (FD-SOI) platforms. The performance of quantum devices is critically dependent on the quality of the material, including the crystalline disorder and processing-induced modifications. Herein, we report a µ-Raman spectroscopy investigation of Si NWs fabricated using dry etching for qubit fabrication. Two different methodologies were used to determine the structural quality of the processed NWs and the presence of stress. First, intentionally localised laser heating of the NW permitted us to decouple the Raman signals of the Si NW and the substrate to extract the NW stress. Second, removing the Si substrate beneath certain NWs enables direct measurement of freestanding Si NW stress. These experimental measurements were supported by finite-element method simulations to analyse the stress profiles correctly. We obtained comparable stress values using both methodologies, ranging from 0.17 to 0.34 GPa, corresponding to small elastic strains (0.1-0.2%) that would lift the heavy-hole/light-hole degeneracy and reduce band mixing. These modifications could favor hole-qubit operation while remaining well below the mechanical stability thresholds. The results confirm the suitability of the etching process for fabricating Si NW-based qubits and establish a reliable platform for robust noninvasive characterisation, even under unfavorable experimental conditions.
Accepted
, Accepted article preview online: 03 July 2026,
doi: 10.37188/lam.2026.116
[PDF](1026)
Chronic wound management requires integrated platforms that combine precise drug delivery, therapeutic stimulation, and continuous monitoring. However, existing microneedle techniques encounter challenges in simultaneously achieving high-precision fabrication, self-powered stimulation-responsive release, and real-time physiological monitoring. In this study, a laser defocusing strategy was developed that utilises energy density variations and plasma shielding effects to enable controllable microneedle mould fabrication. Negative defocusing positions the CO2 laser focal point below the material surface, where the concentrated Gaussian energy distribution enhances the thermal ablation. The plasma shielding effects confine the ablation zone, enabling precise tip formation as small as 2.2 μm. By leveraging this fabrication platform, we created a self-powered microneedle patch for electrical stimulation-triggered drug release, increasing the cumulative amount to approximately 80%. Integrated colorimetric sensors enable the real-time monitoring of wound temperature and pH. In vivo studies demonstrated significantly accelerated wound healing. Through functional integration, this patch fulfils the clinical needs of chronic wound management, making it suitable for personalised therapeutic applications.
Accepted
, Accepted article preview online: 03 July 2026,
doi: 10.37188/lam.2026.118
[PDF](984)
We report the theoretical design and experimental implementation of a wideband all-dielectric mirror that preserves the handedness of incident light upon reflection in the near-infrared range. The mirror consists of a high-contrast, near-subwavelength, one-dimensional dielectric grating placed on a Bragg mirror. We optimised this structure using a genetic algorithm and demonstrated its robustness against geometric imperfections and oblique incidences. The experimental reflection spectra measured under normal incidence on a circular-polarisation basis demonstrated a more than 100-nm-wide reflection band, in which more than 98% of the reflected light preserved its handedness. The total reflection coefficient reached 80%. Furthermore, we demonstrated that the fabricated mirror maintains high performance even under oblique incidence for angles up to \begin{document}$\pm 10^\circ$\end{document}
Accepted
, Accepted article preview online: 01 July 2026,
doi: 10.37188/lam.2026.115
[PDF](1735)
Surface-enhanced Raman spectroscopy (SERS) is a powerful analytical technique for chemical identification that enables trace-level detection across a wide range of applications. However, SERS measurements are typically confined to laboratory environments, requiring a specialised setup and fragile, often single-use, plasmonic substrates. Achieving rugged, reusable SERS measurements, therefore, requires plasmonic substrates with high mechanical robustness and chemical stability. Diamond is an attractive material for this purpose owing to its exceptional mechanical, chemical, and thermal stability and ability to be grown in a laboratory. In particular, it can be used to encapsulate plasmonic nanostructures within a thin film. Robust SERS substrates have been fabricated by encapsulating Ag and Au nanoparticles (NPs) within thin diamond films. Diamond growth conditions control the resulting plasmonic properties, enabling systematic comparison and optimisation of the fabrication parameters. Investigation of Ag- and Au-NPs with diameters of 2-75 nm and diamond film thicknesses of 0 to \begin{document}$ \sim $\end{document} \begin{document}$ \times 10^{3} $\end{document} \begin{document}$ 1 \times 10^{-5} $\end{document}
Accepted
, Accepted article preview online: 01 July 2026,
doi: 10.37188/lam.2026.114
[PDF](1714)
Silicon carbide (SiC) has emerged as a promising integrated platform for quantum and nonlinear photonics owing to its unique combination of a wide bandgap, large Kerr nonlinearity, excellent thermal conductivity, and compatibility with silicon photonics. While progress in fabrication has enabled high-confinement microresonators, achieving industrial-grade, low-loss devices requires overcoming significant manufacturing hurdles related to material defects and surface roughness. This paper provides a comprehensive investigation of advanced manufacturing protocols for wafer-scale (4-inch) 4H-silicon carbide-on-insulator (SiCOI) integrated platforms. This study systematically compares two primary fabrication routes, ion-cut method and bulk wafer thinning, and investigates their impact on material crystal quality and optical loss performance. Using an optimised manufacturing process, we achieved sub-nanometre sidewall roughness and intrinsic quality factors (\begin{document}$Q$\end{document}
Accepted
, Accepted article preview online: 24 June 2026,
doi: 10.37188/lam.2026.109
[PDF](1307)
Graphene-based structures have various prospective applications in optics and photonics. However, most of these applications require fabricating devices on an industrial scale. Currently, this can be achieved using two technologies: chemical vapour deposition (CVD) of graphene on a SiO2 substrate (G-on-SiO2), and epitaxial graphene formed on a SiC substrate (epi-G). In these technologies, graphene is strongly coupled to the substrate, causing it to affect the spatial distribution of the electromagnetic field and optical modes. In this study, we investigated plasmon excitation in the epi-G nanoribbon arrays. We showed that plasmon dispersion in epi-G nanoribbon arrays deviates from that predicted by the analytical model, which works well for G-on-SiO2 structures. Simultaneosly, numerical simulations of epi-G plasmons using the Fourier modal method, which accounted for substrate-induced effects, appeared to agree well with the experimental spectra. We also demonstrated that epi-G structures provide a prospective platform for far- and mid-infrared photonic applications.
Accepted
, Accepted article preview online: 24 June 2026,
doi: 10.37188/lam.2026.111
[PDF](1625)
Structural colour engineering, which involves the manipulation of light at the nanoscale, has emerged as a foundational technology for next-generation intelligent surfaces, moving beyond static displays to enable adaptive, interactive, and multifunctional applications. Emerging from engineered light-matter interactions, it represents a sustainable and dynamically tunable alternative to conventional pigments with transformative potential across advanced technologies. This review provides a comprehensive examination of recent breakthroughs in the nexus between nanofabrication and dynamic modulation technologies for structural colour engineering. Precision mechanical techniques, such as single-point diamond turning and elliptical vibration cutting, enable deterministic subwavelength optical control using programmable toolpaths. Conversely, nonmechanical approaches, such as multiphoton lithography and laser nanostructuring, facilitate the scalable production of functional metasurfaces. Dynamic systems achieve real-time spectral tuning across the visible spectrum through stimuli-responsive mechanisms, including strain-mediated grating reconfiguration and photothermally actuated nanocomposites. These paradigm-shifting advances underpin transformative applications in three key domains: adaptive optical camouflage with environmentally mimicking chromatic shifts, high-security anti-counterfeiting platforms featuring angularly encrypted imagery, and wearable biosensors. However, persistent challenges remain, particularly in reconciling nanoscale precision with industrial scalability, ensuring operational stability under multiphysics field coupling, and expanding the achievable colour spaces. By establishing fundamental connections among photonic design principles, nanofabrication innovations, and stimuli-responsive materials, this analysis outlines an interdisciplinary roadmap for next-generation intelligent surfaces. This ultimately underscores the unique capacity of structural colouration to enable not only eco-friendly but also adaptive and interactive intelligent surface engineering solutions.
Accepted
, Accepted article preview online: 24 June 2026,
doi: 10.37188/lam.2026.110
[PDF](1556)
The continuously increasing demands for high-precision, scalable nanofabrication capabilities motivate the advent of direct-write technologies complementing advanced lithography. Here, we introduce a parallel photonic nanojet (PNJ)-based strategy using microsphere assemblies and angularly scanned, actively tuned femtosecond laser irradiation. By using 5 µm polymer microspheres and 1,030 nm pulses, we generate sub-500 nm PNJs, enabling spatially programmable, ultra-high-density subwavelength patterning on silicon via controlled incidence angles. A key innovation lies in the compensatory laser parameter adjustments, a necessary prerequisite to maintain uniform feature sizes during automated scanning, thus achieving arbitrary nanoscale patterns with a 5 µm pitch. Scalability analysis reveals that mJ-class lasers could parallelize this process across large-area microsphere arrays, producing millions of nanoscale features simultaneously. This approach holds promise for high-throughput, flexible new manufacturing solutions.
Accepted
, Accepted article preview online: 23 June 2026,
doi: 10.37188/lam.2026.108
[PDF](1488)
Microresonator frequency combs typically require multiple coupling paths or auxiliary stabilisation elements, which can increase system complexity and сomplicate scalable photonic integration. Herein, we introduce a self-starting comb architecture in which a single-bus microring resonator, placed within a simple laser cavity comprising only an active fibre and an end mirror, serves as a nonlinear frequency-selective mirror. In our configuration, the optical feedback required to form the laser cavity emanates from resonant Rayleigh backscattering in the microring itself, thus avoiding multiport coupling and external frequency scanning for comb initiation. Using this approach, we experimentally observed self-starting coherent frequency combs with a 1 THz repetition rate, no detectable residual pump, and broadband spectra exceeding 500 nm at a central wavelength of 1550 nm. We verified the concept of integrated Si3N4 microring resonators and crystalline MgF2 toroidal microresonators coupled via tapered fibres, thereby confirming the feedback mechanism. The reflective single-bus topology exhibits robust performance and reduces alignment sensitivity compared with multiport coupling schemes used in some frequency comb implementations. With the further development of active waveguide integration, this architecture may offer a path toward more practical and efficient frequency comb sources in future photonic systems.
Accepted
, Accepted article preview online: 10 June 2026,
doi: 10.37188/lam.2026.097
[PDF](1896)
Recent advancements in smart manufacturing demand wireless power transfer (WPT) systems with dynamic adaptability and miniaturised receivers; however, existing solutions suffer from narrow operational bandwidths and inflexible spatial energy distributions. In this paper, we present a digital metasurface-driven WPT platform that synergises surface plasmon-enhanced coupling with advanced low-temperature cofired ceramic (LTCC) microfabrication. The meta-atom is designed with a wideband configuration and optimised via the magnetoelectric dipole coupling theory. This can enable 180°±5° phase modulation over a 22% fractional bandwidth (5.0–6.25 GHz) and achieve adaptive impedance matching under varying load conditions. A multi-target WPT system is further demonstrated by integrating a digital metasurface, dynamically controlled in real time via a field-programmable gate array, as the energy source, and employing rectennas as receivers corresponding to multiple target positions. The system enables the dynamic shaping of the electromagnetic energy distribution through beam reconfiguration, thus achieving highly directional pencil beams with millisecond-level reconfigurability. The LTCC-based rectenna, leveraging multilayer plasmonic ceramic structures, can attain an RF-to-DC efficiency of 70.5% at 5.8 GHz within an 18 mm×18 mm footprint. Thus, it resolves the efficiency degradation in miniaturised receivers. Experimental results demonstrate that, compared with static metasurface schemes, the proposed system can dynamically switch beam angles and the number of targets in real time, significantly enhancing the spatial energy coverage while maintaining full compatibility with 5G NR standards. This system may pioneer a manufacturing-compatible framework for intelligent metasurface-enabled WPT systems in Internet of Things (IoT) applications.
Accepted
, Accepted article preview online: 06 June 2026,
doi: 10.37188/lam.2026.094
[PDF](1837)
Optical absorption is a performance-limiting factor in high-power laser components. This paper reports the deposition of a series of TiO2-Ta2O5 high-reflection (HR) coatings for 1,064 nm wavelength using electron beam ion-assisted deposition (EB-IAD), followed by thermal annealing at temperatures ranging from 473 to 873 K. The experimental results indicated that the annealing temperature significantly influenced the absorption characteristics of the TiO2-Ta2O5 coatings. Unlike the conventional view that absorption is primarily governed by stoichiometry, this study reveals that although the oxygen vacancy concentration decreases with increasing annealing temperature, typically leading to reduced absorption, the absorption of the coating actually increases beyond a certain annealing temperature threshold. This indicates that factors other than the oxygen vacancies also influence the absorption properties of the film. By combining experimental characterisation, molecular dynamics simulations, and ab initio calculations, we propose that the increase in absorption at higher annealing temperatures is closely connected to structural changes in the coating, particularly localised crystallisation and phase separation within the amorphous TiO2-Ta2O5 film. At the optimal annealing temperature, an HR mirror fabricated using the EB-IAD method exhibited an absorption as low as 1.3 ppm. This work not only deepens the understanding of the absorption mechanisms in composite oxide laser films, but also offers new insights and solutions for the low-cost, large-scale production of high-power laser components.
Accepted
, Accepted article preview online: 02 June 2026,
doi: 10.37188/lam.2026.092
[PDF](1666)
Arthropods' remarkable ability to maintain clear vision in humid environments, owing to the water-repellent and anti-fogging properties of their compound eyes, provides significant inspiration for advancements in optical imaging technology. Metasurfaces, composed of periodically arranged optical nanostructures on a flat surface, can control the wavefront of incident light, leading to lighter and more compact optical integration. For metasurface, a hydrophobic surface is crucial for ensuring long-term operational stability when exposed to outdoor conditions. While protective or hydrophobic coatings can be integrated into metasurface designs by accounting for their refractive indices during the design phase, such coatings would reduce the refractive index contrast for devices based on low-index materials, which necessitate a substantial increase in the nanostructure height to achieve the required phase modulation, thereby increasing fabrication complexity and aspect-ratio requirements. Here, we introduce a method for fabricating low-cost and highly efficient hydrophobic metasurfaces using high-resolution nanoimprint lithography technology. As a proof-of-concept, the light field control capability of the hydrophobic spiral phase plate is demonstrated, the imaging capability of the hydrophobic metalens in harsh environments is explored, and their potential applications in advanced optical systems are demonstrated.
Accepted
, Accepted article preview online: 18 April 2026,
doi: 10.37188/lam.2026.069
[PDF](2886)
High-performance three-dimensional (3D) display technology has been regarded as the future of display technology. However, improving the resolution of the light field 3D display while ensuring full parallax has been a challenge. A light field 3D display based on time-sequential polarization liquid crystal (LC) lens array is proposed to achieve full parallax and high-resolution display. An analysis is conducted on the effect of the frequency response of the lens array on the resolution, and a time-sequential polarization LC lens array is proposed, which improves resolution compared to a microlens array or a lenticular lens array. In addition, the time-sequential polarization LC lens array focuses light in different directions by switching the polarization direction of the incident light. Combined with the parallax-separated pixel encoding method, the proposed light field 3D display achieves a resolution of 1732×1265 and realizes a full parallax with a horizontal and vertical viewing angle of 12.5° by time-division multiplexing. The global resolution is higher than the light field 3D displays based on a lenticular array and a microlens array with the same lens parameters. The polarization conversion layer in the proposed LC lens array can achieve a switching rate of about 208 Hz, which ensures the feasibility of a high frame rate display.
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Published
, Published online: 23 September 2026,
doi: 10.37188/lam.2026.117
Multi-photon polymerization (MPP) is an emerging manufacturing method capable of producing highly detailed, arbitrarily shaped three-dimensional micro- and nanostructures with feature sizes of single elements below 100 nm. MPP conventionally relies on ultrashort pulse laser systems operating at peak powers in the kilowatt to tens of kilowatt regime and with peak intensities in the range of TW/cm2 to achieve sufficient nonlinear absorption. As a novel approach, here we demonstrate that lasers with significantly lower peak powers and lower peak intensities can also be utilized for MPP at high processing speeds, employing a novel monolithically integrated mode-locked diode laser with 30 W peak power, 7.7 ps pulse length, and a 13.2 GHz repetition rate which could achieve peak intensities of 23 GW/cm2. It is conceivable that the lower peak intensity may be partially compensated for by the considerably higher repetition rate. However, whether this type of compensation is applicable is unclear due to the inherent non-linear MPP process, and requires experimental verification in this work. Using this diode laser prototype, complex 3D structures at scan speeds of up to 100 mm/s were fabricated, achieving rapid production without compromising structural detail. Furthermore, the minimum achievable feature size was assessed through single-line scan experiments at various speeds, obtaining voxel dimensions of down to 121 nm in width and 151 nm in height. Our results suggest that diode laser-based MPP systems can deliver competitive processing performance with a more compact, much less complex, and more cost-effective laser source. This advancement paves the way for scalable parallel multi-laser MPP processing and may significantly accelerate the broader adoption of MPP technology.
Published
, Published online: 23 September 2026,
doi: 10.37188/lam.2026.070
Efficient terahertz (THz) wave manipulation is essential for advancing communications, imaging, and security detection. However, conventional THz devices based on natural materials suffer from the issues of bulky size, low efficiency, and narrow bandwidth. Although dielectric metasurfaces offer a promising alternative, their practical applications still face challenges in high-precision manufacturing, particularly for structures with high aspect-ratio (AR) and deep etching depth. Herein, we experimentally construct high-quality silicon meta-devices for THz wave-controls. Guided by the analysis of the potential structural imperfections, we propose an optimized fabrication method based on the Bosch etching technology to address these challenges and create silicon meta-atoms with high AR and vertical sidewall. As a proof-of-concept, we design and fabricate a half-wave plate (HWP) and a quarter-wave plate (QWP) with a maximum AR of 19.2:1 and broad working bands (0.6–0.8 THz and 0.5–0.8 THz). Their polarization conversion ratios (PCRs) can reach 0.915 and 0.99 at approximately 0.73 THz and 0.66 THz, respectively. Furthermore, we experimentally realize a highly efficient and broadband metalens exhibiting the high average focusing efficiency of 85.56% within 0.6–0.8 THz. Our fabrication methodology can be extended to fabricate other high-performance metasurfaces, opening new possibilities for broadband THz applications.
Published
, Published online: 23 September 2026,
doi: 10.37188/lam.2026.100
As semiconductor process nodes advance, the interaction between electromagnetic waves and mask three-dimensional topography becomes increasingly significant. Curvilinear masks with superior process windows are being rapidly adopted, exposing the limitations of existing thick-mask models in accommodating arbitrary curvilinear edges. Therefore, a theoretical framework for the full-chip-scale, rapid modelling of curvilinear thick masks is required. This paper introduces a physically covariant curvilinear thick-mask model based on edge diffraction correction for rapid full-chip layout simulation. The model decomposes the mask response into a thin-mask approximation term and an edge diffraction correction term. Through rigorous mathematical derivation, the diffraction response of the reference mask edges is decomposed into physically meaningful two-dimensional differential edge diffraction kernels. Furthermore, the edge diffraction term of full-chip layouts is efficiently reconstructed via a multi-channel tensor convolution framework, thereby correcting the thin-mask approximation and establishing the curvilinear thick-mask model. Simulation results demonstrated that, compared with finite-difference time-domain benchmarks, the proposed model achieved curvilinear mask near-field root mean square errors below 0.03 while delivering a speed-up of over 2,600 times. Moreover, it provided more than 2× error reduction over traditional Manhattanisation curvilinear models and maintained superior physical covariance. This study is expected to provide robust support not only for efficient and accurate forward modelling in resolution-enhancement techniques, such as inverse lithography technology and source mask optimisation, but also for the optical characteristic fast simulation of metasurfaces and metamaterials.
Published
, Published online: 18 September 2026,
doi: 10.37188/lam.2026.095
Carbon materials have significant scientific and application potential in the terahertz field. Metasurfaces are considered the core components of next-generation of terahertz photonic systems. The introduction of advanced carbon-based fabrication techniques operating with high efficiency and low complexity is essential for the development of terahertz metasurface photonic devices. In this study, we demonstrate a carbon-based manufacturing approach. This relies on a dual-mode additive manufacturing technique and can be used to directly print subwavelength resonant structures on flexible substrates. We demonstrate the preparation method and properties of different carbon nanocomposite inks. In addition, we present printing parameter configurations and printing results. To demonstrate their effectiveness, two carbon-based metasurface terahertz absorbers and a terahertz filter are designed and fabricated. The resonant structures are printed directly onto different flexible substrates using different printing modes. A fibre-based terahertz spectroscopy system is built to test the samples. The test results meet the expectations and are consistent with the simulations. By enabling the low complexity of carbon-based additive manufacturing and offering flexibility in flexible substrate choice and resonant-pattern design, the approach could facilitate terahertz metasurface technologies for real-world applications.
Published
, Published online: 18 September 2026,
doi: 10.37188/lam.2026.107
Photonic integrated circuits (PICs) are expected to overcome the intrinsic bottleneck faced by conventional electronic circuits, enabling substantial improvements in bandwidth capacity and data processing speed. Nevertheless, the on-chip integration of lasers remains a critical challenge hindering the development of PICs. Furthermore, conventional photonic devices exhibit large feature sizes and inter-component separation distances on the order of tens of micrometres, resulting in a low integration density. In this study, an ultracompact integrated photonic logic chip is proposed for all-optical information processing. The integrated architecture comprises a III-V micro-laser, four hybrid Bi2Te3-Si micro-ring resonators, and inverse-designed structures. The nonlinear material Bi2Te3 coated on the Si micro-ring resonators achieved optical tunability. The components are interconnected via waveguides and inverse-designed structures with a compact intercomponent distance of merely 1.5 μm. Pump–probe measurements reveal hundreds of femtoseconds of transient responses in the hybrid Bi2Te3-Si resonant elements, whereas the integrated chip experimentally demonstrates two-bit optical logic operations enabled by the hybrid resonators and integrated micro-laser. This study presents a novel technical solution for the implementation of fully on-chip integrated photonic circuits and establishes a new research paradigm for the development of ultrahigh-integration-density photonic chips.
Published
, Published online: 18 September 2026,
doi: 10.37188/lam.2026.120
Efficient light harvesting from front and rear sides is essential for improving solar energy utilisation in applications such as photovoltaics and seawater desalination. This requires absorbers that exhibit strong double-sided absorption in the ultraviolet to near-infrared range, mechanical flexibility for transfer onto diverse substrates, reliable performance stability, and manufacturing scalability for practical deployment. However, these capabilities are difficult to achieve simultaneously using conventional thin-film or metamaterial absorbers. In this study, we developed a double-sided bioinspired metamaterial absorber (DS-BMA) composed of a single layer of chromium (Cr) nano-units, whose front and back surfaces mimic the morphologies of moth eyes and marine diatoms, respectively. The gradient geometric configuration of the DS-BMA significantly broadened the bandwidths of plasmonic resonances, thereby enabling near-perfect absorption over the entire solar spectrum. Using a scalable self-assembly-based process, we experimentally showed a flexible, transferable DS-BMA with a thickness of 500 nm. It achieved average absorptances of 93% and 96% on the front and back sides, respectively, over a wavelength range of 220–2,500 nm. The DS-BMA exhibited polarisation-independent omnidirectional absorption as well as excellent thermal stability, corrosion resistance, and mechanical robustness. Therefore, the DS-BMA provides a promising route toward high-efficiency, low-cost, and integrable photothermal/photovoltaic energy conversion devices.
Published
, Published online: 16 September 2026,
doi: 10.37188/lam.2026.128
Additive manufacturing using 2-Photon Polymerization (2PP, aka direct laser writing DLW) enables the fabrication of almost arbitrary complex 3D structures from the meso to the sub-micron scale. However, deviations between the anticipated target structure and the actual print often occur due to physico-chemical processes, limiting the accuracy and reliability of this technology. To minimize these deviations, we hereby present our latest research in developing different neural networks, targeting the above-mentioned aspect. Our networks are trained on several experimental as well as theoretical datasets and show good results in predicting fabrication deviations and (pre-) correcting 2.5D μ-structures. Hence, we demonstrate, that besides conventional iterative correction methods, neural networks are a promising alternative to significantly improving the output quality in DLW. First directly pre-corrected structures show a reduction of the root mean square error up to 93% in the best case scenario. Furthermore, there are no fundamental limitations to transferring this machine learning approach to other 3D printing technologies, as they all face the same challenge in terms of fidelity. To our point of view, the use of neural networks has the potential to enhance the capabilities of this technology, enabling the creation of complex structures with increased accuracy and precision in the near future.
Published
, Published online: 09 September 2026,
doi: 10.37188/lam.2026.112
Table-top extreme ultraviolet (EUV) reflection ptychography has gained increasing interest in semiconductor metrology due to its nanometer-scale resolution, nondestructive character, and laboratory-scale cost-effectiveness. However, its widespread adoption remains constrained by alignment challenges inherent to grazing-reflection geometry, which have prevented reflective configurations from achieving image quality comparable to those of transmission-mode systems. In this study, we introduce a table-top EUV grazing-reflection ptychography system that enables full-pose self-calibration through holistic system modeling and highly efficient optimization. The developed system is validated using a customized wafer sample and real chip sample. Experimental results indicate that the system successfully corrects image distortions, improves resolution, and enhances surface metrology quality. Furthermore, we discuss algorithmic and physical issues including the feature-domain phase-retrieval for ptychography and coupling effect among pose parameters. The proposed approach not only accelerates the transition of EUV reflection ptychography toward real-world use but also opens avenues for methodological advances to a wider range of imaging applications.
Published
, Published online: 08 September 2026,
doi: 10.37188/lam.2026.090
Phase-shifting interferometry underpins surface topography metrology in precision fields such as semiconductor manufacturing and optical engineering. However, its reliance on stringent vibration isolation and precise phase-shifting control restricts its applicability in many scenarios, particularly in the characterisation of large-aperture optical components. To address these limitations, we present disturbance-introduced interferometry, which harnesses ambient random mechanical disturbances as phase-shifting sources. We also develop a large-disturbance-adaptive natural phase decoding algorithm to reconstruct the surface topography from the resulting interferograms. This framework reduces reliance on stringent vibration isolation and precise phase-shifting control, making it particularly suitable for large-aperture surface metrology and measurements in vibration-prone manufacturing environments. Experimental results demonstrated that even in uncontrolled and vibration-prone environments, the method achieves a root-mean-square wavefront repeatability below 0.0018\begin{document}$ \lambda $\end{document} \begin{document}$ \lambda $\end{document} \begin{document}$ \lambda $\end{document} \begin{document}$ \lambda $\end{document} \begin{document}$ \lambda $\end{document}
Published
, Published online: 07 September 2026,
doi: 10.37188/lam.2026.105
An achromatic metalens (480–640 nm) was designed via integrating propagation and geometric phase principles and fabricated using one-step nanoimprint lithography (NIL). A novel nanoimprint photoresist was used, which not only has a high refractive index (1.92–1.97) and high transmittance (>99%) but also exhibits low shrinkage (≤5.19%). This low shrinkage results in small dimensional deviations of the meta-atoms relative to the NIL master. The working stamp was fabricated in 10 min using an ultraviolet-curable material. This process is much faster than polydimethylsiloxane-based alternatives, which require several hours of thermal curing. Owing to its high fabrication accuracy, the metalens exhibited excellent focusing and achromatic performance, with a wavelength-dependent focal-length deviation of <2%. This study has provided a potential route for the high-precision, high-efficiency, and large-scale production of achromatic metalenses and other nano/micro-optical devices.
Published
, Published online: 01 September 2026,
doi: 10.37188/lam.2026.013
The rapid evolution of high-end technologies demands optical manufacturing with low cost, high efficiency, and superior performance. Existing sub-aperture polishing paradigms rely on a stable tool influence function (TIF) and control material removal by convolving dwell time along the path. However, regulating only dwell time creates an inherent trade-off between removal efficiency and fabrication accuracy, introducing mid-spatial-frequency errors. This paper proposes an innovative manufacturing paradigm based on the immersion depth and scanning speed dynamic co-variation (IDSS-DC) model, establishing an adjustable mechanism for the TIF. A novel dual-degree-of-freedom coordinated control paradigm is developed to simultaneously achieve high efficiency and superior fabrication quality. The influence of immersion depth on removal efficiency is derived, facilitating spatiotemporal control of the TIF in efficiency and profile, allowing optimization of multi-spatial-frequency errors within a single pass. Additionally, a dwell time solution method using constant-variable speed dual-mode (CVSDM) driven by actively controllable spatiotemporally variable TIF (ACSV TIF) accelerates error convergence. Magnetorheological finishing experiments and simulations show that the IDSS-DC model surpasses the traditional paradigm improving accuracy by nearly 10% and reducing processing time by more than 30%. The results demonstrate efficient and stable convergence of multi-spatial-frequency errors, providing an innovative manufacturing paradigm for nanometer-level precision and high-efficiency optical fabrication.
Published
, Published online: 28 August 2026,
doi: 10.37188/lam.2026.121
Structured illumination microscopy (SIM) doubles the lateral resolution compared with wide-field fluorescence microscopy. However, the fast modulation of structured illumination patterns is typically highly dependent on pixelated digital devices, which suffer from low optical efficiency, self-diffraction noise, and high costs. Here, we present a Sector-Rotational SIM (Sero-SIM), which integrates the modulation of the illumination direction and phase shift into a single sector-rotational transmissive grating, achieving an approximately twofold resolution enhancement at a very low cost and minimal control complexity. Moreover, by incorporating a pyramidal lens into the optical setup, we decouple the sector size from the field of view (FOV), expanding the FOV by more than 13 times. We evaluated the performance of Sero-SIM using high-fidelity imaging of diverse subcellular structures in both fixed samples and live cells. The capability of large-FOV super-resolution imaging endows Sero-SIM with a strong potential for applications spanning multiple spatial scales, from pathological tissues and cell populations to single cells and subcellular organelles. Altogether, Sero-SIM introduces a distinctive and practical approach for SIM implementation.
Published
, Published online: 22 August 2026,
doi: 10.37188/lam.2026.099
Refractory high-entropy alloys (RHEAs) have attracted considerable interest owing to their excellent mechanical strength and thermal stability. However, their inherent brittleness and low thermal conductivity pose significant challenges for high-precision micromachining at room temperature. Conventional nanosecond lasers (CNL) and wire-electrode cutting inevitably cause severe thermal damage and reduce machining quality. In this study, water-jet guided laser (WJGL) technology was utilised for the precision machining of a carbide-reinforced NbMoTaW RHEA. Benefiting from synergistic ablation, cooling, and debris removal effects, WJGLs enable a much cleaner machining interface with minimal spattering compared with CNL and femtosecond lasers. Notably, WJGLs reduced the heat-affected zone to 298 nm, which was ~99.1% lower than that of the CNL. A minimum drilling taper of 0.014° was achieved, indicating ultrahigh micromachining precision. The material removal mechanism and microstructural evolution were elucidated. This study provides a reliable approach for the precision manufacturing of hard-to-process RHEAs.
Published
, Published online: 22 August 2026,
doi: 10.37188/lam.2026.084
Ultrafast laser processing has emerged as a powerful tool for high-precision 3D microfabrication due to its ability to induce localised structural modifications in transparent materials by non-linear multi-photon absorption. In this study, we demonstrated high-precision parallel laser processing by individual axial control of two laser focal spots using a single focusing lens. The proposed method was based on the divergence focus control (DFC) concept, where the focal spot position along the beam axis in the material volume could be controlled by tailoring the laser beam divergence. Numerical simulations confirmed the influence of the axial shift in response to variations in the laser beam divergence. In addition, ray-tracing propagation combined with vector diffraction theory was used to evaluate the influence of spherical aberrations and partial aperture filling on the focal spot morphology and spatial intensity distribution. Experiments were carried out and the results showed that axial focal shifts exceeding 900 µm were achieved by only using a standard microscope objective with a numerical aperture of 0.4. Furthermore, individual control of the two focal points was attained, allowing parallel laser writing with high precision inside transparent materials. For experimental validation, a pair of parallel patterns with different axial distances was fabricated on photosensitive glass, which exhibited high controllability. This method provides a scalable and compact solution for parallel 3D microfabrication and offers advantages such as reduced costs, ease of operation, and straightforward integration into the existing experimental set-up compared with other conventional focusing strategies.
Published
, Published online: 22 July 2026,
doi: 10.37188/lam.2026.098
Diffraction-limited synchrotron sources place stringent demands on wavefront-preserving X-ray optics. We report a fully in-house, closed-loop pipeline at the National Synchrotron Light Source II that links ion beam figuring, precision ex situ metrology, wavefront simulation, and in situ beam validation. The fabricated elliptical Kirkpatrick–Baez mirrors achieved 0.4 nm root-mean-square residual height error. At 12 keV, ptychography measured a 70.5 × 33.1 nm2 (V × H) focal spot using an 8 × 7 µm2 secondary source aperture, consistent with partially coherent Synchrotron Radiation Workshop simulations of 77 × 36 nm2. X-ray fluorescence imaging independently resolved approximately 30 nm features in a Siemens star. Back-propagation of the reconstructed probe further linked the measured wavefront to ex situ surface errors, establishing quantitative closure across fabrication, metrology, simulation, and beamline commissioning.
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Published
, Published online: 15 September 2026,
doi: 10.37188/lam.2026.106
As the pivotal patterning technique in integrated circuit manufacturing, optical lithography is the principal driver of Moore’s Law. However, at advanced technology nodes, lithography confronts fundamental challenges from diffraction effects, equipment bottlenecks, and stochastic process variations, which severely narrow the process window and impede manufacturing yield. Curvilinear mask technology, an approach derived from inverse lithography technology, has emerged as a potential solution to transcend these limitations. This study provides a comprehensive overview of the technology, detailing its underlying principles and advantages in manufacturing and design, analysing its application scenarios and current challenges, and reviewing the progress and future directions of its key enabling technologies.
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Published
, Published online: 23 September 2026,
doi: 10.37188/lam.2026.130
Existing three-dimensional fibre shape-sensing systems involve trade-offs among compactness, spatial sampling density, and interrogation complexity. Luo et al. addressed these challenges by spatially encoding orthogonal curvature components using axially misplaced eccentric scatterers in a standard single-mode fibre, enabling millimetre-scale, single-channel reconstruction and scalable integration into robotic and minimally invasive devices.
Published
, Published online: 11 September 2026,
doi: 10.37188/lam.2026.126
A biphasic chiral photonic crystal has been shown to support four structurally orthogonal encryption keys by exploiting physical and optical orthogonality. These results open new opportunities to engineer combinatorial key spaces in photonic platforms and for applications in optical security and anti-counterfeiting.
ISSN 2689-9620 EISSN 2831-4093
Indexed by:
- ESCI (IF 10.2)
- DOAJ
- Scopus
- Google Scholar
- CNKI
- CSCD
- CSTPCD
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2023, 4(2): 143-167. doi: 10.37188/lam.2023.011
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2022, 3(3): 572-600. doi: 10.37188/lam.2022.035
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2023, 4(4): 519-542. doi: 10.37188/lam.2023.031
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2021, 2(1): 59-83. doi: 10.37188/lam.2021.005
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2024, 5(1): 117-132. doi: 10.37188/lam.2024.005
