View by Category
Published
, Published online: 03 March 2026
, doi: 10.37188/lam.2026.029
Mid-infrared (MIR) refractive index (RI) sensing holds significant potential for applications in chemical detection, environmental monitoring, and biomedical diagnostics due to the strong molecular vibrational fingerprints in this spectral range. However, conventional metasurface-based sensors face challenges in fabrication complexity, toxic solvents, and performance optimization. Here, we introduce ice-lithographed 2.5-dimensional (2.5D) plasmonic metasurfaces featuring vertically asymmetric gold cross-pillar resonators to overcome these challenges. The solvent-free ice lithography enables in situ scanning electron microscopy (SEM) alignment with high precision, residue-free surfaces, and multilayer stacking in a single vacuum process. Simulations reveal that vertically graded pillars (height 0–800 nm) linearly redshift resonance wavelengths while concentrating electric fields at analyte-binding sites, boosting experimentally measured sensitivity from 735 nanometers per refractive index unit (nm/RIU) to 2 266 nm/RIU. This work demonstrates a three-dimensional (3D) architectural strategy for enhancing sensing performance, while simultaneously unveiling the potential of ice lithography in fabricating low-toxicity and flexible 2.5D sensing devices.
Published
, Published online: 29 January 2026
, doi: 10.37188/lam.2026.003
The efficient and robust joining of transparent metal-dissimilar materials remains a significant challenge in high-performance system integration. A primary barrier is the inherently rough surfaces of metals, which hinder reliable bonding with transparent materials, largely due to the limited understanding of the underlying welding mechanisms. In this study, we demonstrate ultrafast laser joining between sapphire and metal substrates with surface roughness (Sa) up to 2 μm, achieving a maximum shear strength of 11.73 MPa. High-speed imaging techniques were employed to conduct the first systematic investigation of coupled absorption dynamics at heterogeneous interfaces. The plasma ejection observed during welding indicated that the molten metal actively confined the interfacial region, transforming the initial free space into a confined space. This transition facilitates the formation of an optical contact condition, significantly improving the joint strength. To further explore the potential of pulse shaping in controlling interfacial behaviour, the effects of temporal shaping (Burst mode) on laser energy deposition, joint strength, and interfacial morphology were examined. Consistent joint quality was achieved across a range of burst parameters, with shear strengths ranging from 9 to 13 MPa. Fractographic analysis indicated that the fracture was predominantly governed by the internal stress within the sapphire, thereby limiting further improvements in joint strength. The revelation of the ultrafast laser welding mechanism for non-optical contact dissimilar materials, along with the exploration of temporal shaping for enhancing welding performance, offers theoretical insights and technical guidance for the development of high-performance heterogeneous material joining.
Published
, Published online: 12 January 2026
, doi: 10.37188/lam.2026.002
Photodynamic therapy (PDT) is a promising strategy for treating solid tumours due to its spatially controlled, light-triggered cytotoxicity. Although recent advances in optical technologies have improved light delivery, PDT efficacy remains limited by insufficient drug accumulation in tumours, largely due to the complexity of the tumour microenvironment. To address this challenge, a macrophage-mediated delivery platform was developed using layer-by-layer (LbL) microcapsules loaded with second-generation photosensitizers: photoditazine (PD) and aluminum tetrasulfophthalocyanine chloride (PS). Both photosensitizers exhibited low dark toxicity and high phototoxicity, enabling their safe transport by carrier cells. The photosensitizers were efficiently encapsulated into LbL microcapsules (6.2 ± 0.5 μm) with different shell compositions. Significant differences were observed between macrophage types: RAW 264.7 macrophages predominantly retained capsules on the cell surface, whereas primary peritoneal macrophages (PMs) internalised capsules within 3 h and retained them for up to 6 d without degradation. Among the tested formulations, polyarginine/dextran sulfate ((PArg/DS)4) capsules loaded with PD demonstrated the highest uptake efficiency and supported macrophage migration into tumour spheroids. In vivo experiments using a CT-26 colon cancer model confirmed the therapeutic potential of this platform, while highlighting the need for further optimisation for large tumours. This study provides new insights into cell-mediated delivery systems and underscores their potential to enhance PDT outcomes beyond current limitations.
Published
, Published online: 31 March 2021
, doi: 10.37188/lam.2021.006
Future quantum technology relies crucially on building quantum networks with high fidelity. To achieve this challenging goal, it is of utmost importance to connect individual quantum systems such that their emitted single photons overlap with the highest possible degree of coherence. This requires perfect mode overlap of the emitted light from different emitters, which necessitates the use of single-mode fibres. Here, we present an advanced manufacturing approach to accomplish this task. We combined 3D printed complex micro-optics, such as hemispherical and Weierstrass solid immersion lenses, as well as total internal reflection solid immersion lenses, on top of individual indium arsenide quantum dots with 3D printed optics on single-mode fibres and compared their key features. We observed a systematic increase in the collection efficiency under variations of the lens geometry from roughly 2 for hemispheric solid immersion lenses up to a maximum of greater than 9 for the total internal reflection geometry. Furthermore, the temperature-induced stress was estimated for these particular lens dimensions and results to be approximately 5 meV. Interestingly, the use of solid immersion lenses further increased the localisation accuracy of the emitters to less than 1 nm when acquiring micro-photoluminescence maps. Furthermore, we show that the single-photon character of the source is preserved after device fabrication, reaching a \begin{document}$ g^{(2)} (0)$\end{document} ![]()
![]()
Email
RSS