The optimal orientations are determined for polarized substrate side illumination of three superconducting nanowire single-photon detector (SNSPD) designs: (1) periodic niobium-nitride (NbN) stripes standing in air with dimensions according to conventional SNSPDs, (2) same NbN patterns below ~quarter-wavelength hydrogensilsesquioxane-filled nano-cavity, (3) analogous NbN patterns in HSQ nano-cavity closed by a thin gold reflector. Numerical computation results have shown that the optical response and near-field distribution vary significantly with polar-angle, fi, and these variations are analogous across all azimuthal-angles, gamma, but are fundamentally different in various device designs. Larger absorptance is available due to p-polarized illumination of NbN patterns in P-structure configuration, while s-polarized illumination results in higher absorptance in S-structure arrangement. As a result of p-polarized illumination a global maximum appears on absorptance of bare NbN pattern at polar angle corresponding to NbN-related ATIR; integration with HSQ nano-cavity results in a global absorptance maximum at polar angle corresponding to TIR at sapphire-air interface; while the highest absorptance is observable at perpendicular incidence on P-structures aligned below gold reflector covered HSQ nano-cavity. S-polarized light illumination results in a global absorptance maximum at TIR on bare NbN patterns; the highest absorptance is available below HSQ nano-cavity at polar angle corresponding to ATIR phenomenon; while the benefit of gold reflector is large and polar angle independent absorptance.
We report a quantitative analysis of the wavevector diagram emitted by nonlinear photoluminescence generated by a tightly focused pulsed laser beam and distributed along Au nanowire via the mediation of surface plasmon polaritions. The nonlinear photoluminescence is locally excited at key locations along the nanowire in order to understand the different contributions constituting the emission pattern measured in a conjugate Fourier plane of the microscope. Polarization-resolved measurements reveal that the nanowire preferentially emits nonlinear photoluminescence polarized transverse to the lo…
Coupling of two dielectric wires with rectangular cross-section gives rise to bonding and anti-bonding resonances. The latter is featured by extremal narrowing of the resonant width for variation of the aspect ratio of the cross-section and distance between wires when the morphology of the anti-bonding resonant mode approaches to the morphology of the Mie resonant mode of effective circular wire with high azimuthal index. Then plane wave resonant to this anti-bonding resonance gives rise to unprecedent enhancement of the optical forces up to several nano Newtons per micron length of wires. The…
Semi-transparent photovoltaics (ST-PV) provide smart spatial solutions to integrate solar cells into already-built areas. Here, we study the potential of semiconductor nanowires (NWs) as promising ST-PV. We perform FDTD simulations for different PV materials in a wide range of array geometries, from which we compute PV performance next to perceived appearance. Surprisingly we find an unusual compromise between photocurrent and transmittance as a function of NW diameter that enables NW-based PV to outperform theoretical limits of non-wavelength selective ST-PV. We theoretically and experimental…
We present an approach to increase the effective light-receiving area of superconducting nanowire single-photon detectors (SNSPD) by means of free-form microlenses that are printed in situ on top of the sensitive detector area using high-resolution multi-photon lithography. We demonstrate a detector based on a niobium-nitride (NbN) nanowire with a 4.5 $\mathrm μ$m $\times$ 4.5 $\mathrm μ$m sensitive area, supplemented with a lens of 60 $\mathrm μ$m diameter. For free-space illumination at a wavelength of 1550 nm, the lensed sensor has a 100-fold-increased effective collection area, which leads…
Designing directional optical antennas without compromising the field enhancement requires specially designed optical cavities. Herein, we report on the experimental observations of directional photoluminescence emission from a monolayer Tungsten Disulfide using a bent-plasmonic nanowire on a mirror cavity. The geometry provides field enhancement and directivity to photoluminescence by sandwiching the monolayer between an extended cavity formed by dropcasting bent silver nanowire and a gold mirror. We image the photoluminescence emission wavevectors by using the Fourier plane imaging technique…
Spectral engineering via complex patterns of circular nano-object miniarrays: II. concave patterns tunable by integrated lithography realized by circularly polarized light
UV-enhanced SEM: towards orientation and electron work function imaging
Research Institute of Electronics, Shizuoka University（静冈大学电子研究所）；Optical Sciences Centre, School of Science, Swinburne University of Technology（斯威本科技大学理学院光学科学中心）；Extreme Light Infrastructure (ERIC)（极端光基础设施（ERIC））；Graduate School of Science and Technology, Shizuoka University（静冈大学理工学研究科）；Faculty of Engineering, Shizuoka University（静冈大学工学部）；World Research Hub Initiative (WRHI), Institute of Science Tokyo, School of Materials and Chemical Technology（东京科学大学材料化学技术学部世界研究枢纽倡议项目）；Laser Research Center, Physics Faculty, Vilnius University（维尔纽斯大学物理学院激光研究中心）
Spectral engineering via complex patterns of circular nano-object miniarrays: I. convex patterns tunable by integrated lithography realized by circularly polarized light
3D scattered light imaging: extracting 3D fiber orientations from 1D line profiles in brain imaging
Forschungszentrum Juelich（于利希研究中心）；University of Wuppertal（伍珀塔尔大学）；University of Twente（特文特大学）；Netherlands Institute for Neuroscience, Royal Netherlands Academy of Arts and Sciences（荷兰神经科学研究所，荷兰皇家艺术与科学院）
