Recent advances in engineered material technologies(e.g.,photonic crystals,metamaterials,plasmonics,etc.)provide valuable tools to control Cherenkov radiation.In all these approaches,however,the particle velocity is a...Recent advances in engineered material technologies(e.g.,photonic crystals,metamaterials,plasmonics,etc.)provide valuable tools to control Cherenkov radiation.In all these approaches,however,the particle velocity is a key parameter to affect Cherenkov radiation in the designed material,while the influence of the particle trajectory is generally negligible.Here,we report on surface Dyakonov-Cherenkov radiation,i.e.the emission of directional Dyakonov surface waves from a swift charged particle moving atop a birefringent crystal.This new type of Cherenkov radiation is highly susceptible to both the particle velocity and trajectory,e.g.we observe a sharp radiation enhancement when the particle trajectory falls in the vicinity of a particular direction.Moreover,close to the Cherenkov threshold,such a radiation enhancement can be orders of magnitude higher than that obtained in traditional Cherenkov detectors.These distinct properties allow us to determine simultaneously the magnitude and direction of particle velocities on a compact platform.The surface Dyakonov-Cherenkov radiation studied in this work not only adds a new degree of freedom for particle identification,but also provides an all-dielectric route to construct compact Cherenkov detectors with enhanced sensitivity.展开更多
Surface-wave-based optical sensing of an analyte in a fluid relies on the sensitivity of the surface wave to the electromagnetic properties of the analyte-containing fluid in the vicinity of the guiding interface. Sur...Surface-wave-based optical sensing of an analyte in a fluid relies on the sensitivity of the surface wave to the electromagnetic properties of the analyte-containing fluid in the vicinity of the guiding interface. Surfaceplasmon-polariton(SPP) waves are most commonly used for optical sensing because of the ease of the excitation of an SPP wave when the fluid is partnered with a metal. If the fluid is replaced by a porous, anisotropic, and periodically nonhomogeneous solid filled with the fluid, while the metal is replaced by an isotropic homogeneous dielectric material, the surface wave is called a Dyakonov–Tamm(DT) wave. We have theoretically determined that the incorporation of the DT-waveguiding interface in a prism-coupled configuration provides an alternative to the analogous SPP wave-based sensor, with comparable dynamic sensitivity.展开更多
基于Dyakonov-Shur效应（D-S效应）利用MOSFET可构建太赫兹源。研究表明MOSFET沟道内的1 m V信号在偏置电压的作用下产生波动并形成等离子波,其电学特性与谐振腔相似。当MOSFET外接5 V的偏置电压源时,输出频率为2.15 THz、峰值为2 m V...基于Dyakonov-Shur效应（D-S效应）利用MOSFET可构建太赫兹源。研究表明MOSFET沟道内的1 m V信号在偏置电压的作用下产生波动并形成等离子波,其电学特性与谐振腔相似。当MOSFET外接5 V的偏置电压源时,输出频率为2.15 THz、峰值为2 m V的等离子信号。通过调节偏置电压（1-20 V）可以使输出信号在0.96-4.30 THz范围内调频。此外,MOSFET在5 V的偏置电压和5 A的偏置电流的共同作用下,沟道内产生的等离子波随时间的推移以指数形式放大。受器件限制和沟道夹断效应影响,该信号源的最大输出电压为20 V,电压增益最大可达到86 d B,最大输出功率为200 W。在器件允许范围内,偏置电压越大信号频率越高、偏置电流越大起振时间越短,且偏置电流引起的信号频偏小。展开更多
基金Y.L.was sponsored in part by Singapore Ministry of Education(No.MOE2018-T2-2-189(S)),MOE2017-T1-001-239(RG91/17(S)),A*Star AME Programmatic Funds(No.A18A7b0058)and National Research Foundation Singapore Competitive Research Program(No.NRF-CRP18-2017-02)B.Z.was sponsored in part by Singapore Ministry of Education(No.MOE2018‐T2‐1‐022(S),MOE2016‐T3‐1‐006 and Tier 1 RG174/16(S))+3 种基金L.J.W.was sponsored in part by the Advanced Manufacturing and Engineering Young Individual Research Grant(No.A1984c0043)from the Science and Engineering Research Council of the Agency for Science,Technology and Research,SingaporeX.L.was sponsored in part by the National Natural Science Foundation of China(NSFC)(No.62175212)Fundamental Research Funds for the Central Universities(No.2021FZZX001-19)Zhejiang University Global Partnership Fund.
文摘Recent advances in engineered material technologies(e.g.,photonic crystals,metamaterials,plasmonics,etc.)provide valuable tools to control Cherenkov radiation.In all these approaches,however,the particle velocity is a key parameter to affect Cherenkov radiation in the designed material,while the influence of the particle trajectory is generally negligible.Here,we report on surface Dyakonov-Cherenkov radiation,i.e.the emission of directional Dyakonov surface waves from a swift charged particle moving atop a birefringent crystal.This new type of Cherenkov radiation is highly susceptible to both the particle velocity and trajectory,e.g.we observe a sharp radiation enhancement when the particle trajectory falls in the vicinity of a particular direction.Moreover,close to the Cherenkov threshold,such a radiation enhancement can be orders of magnitude higher than that obtained in traditional Cherenkov detectors.These distinct properties allow us to determine simultaneously the magnitude and direction of particle velocities on a compact platform.The surface Dyakonov-Cherenkov radiation studied in this work not only adds a new degree of freedom for particle identification,but also provides an all-dielectric route to construct compact Cherenkov detectors with enhanced sensitivity.
文摘Surface-wave-based optical sensing of an analyte in a fluid relies on the sensitivity of the surface wave to the electromagnetic properties of the analyte-containing fluid in the vicinity of the guiding interface. Surfaceplasmon-polariton(SPP) waves are most commonly used for optical sensing because of the ease of the excitation of an SPP wave when the fluid is partnered with a metal. If the fluid is replaced by a porous, anisotropic, and periodically nonhomogeneous solid filled with the fluid, while the metal is replaced by an isotropic homogeneous dielectric material, the surface wave is called a Dyakonov–Tamm(DT) wave. We have theoretically determined that the incorporation of the DT-waveguiding interface in a prism-coupled configuration provides an alternative to the analogous SPP wave-based sensor, with comparable dynamic sensitivity.
文摘基于Dyakonov-Shur效应（D-S效应）利用MOSFET可构建太赫兹源。研究表明MOSFET沟道内的1 m V信号在偏置电压的作用下产生波动并形成等离子波,其电学特性与谐振腔相似。当MOSFET外接5 V的偏置电压源时,输出频率为2.15 THz、峰值为2 m V的等离子信号。通过调节偏置电压（1-20 V）可以使输出信号在0.96-4.30 THz范围内调频。此外,MOSFET在5 V的偏置电压和5 A的偏置电流的共同作用下,沟道内产生的等离子波随时间的推移以指数形式放大。受器件限制和沟道夹断效应影响,该信号源的最大输出电压为20 V,电压增益最大可达到86 d B,最大输出功率为200 W。在器件允许范围内,偏置电压越大信号频率越高、偏置电流越大起振时间越短,且偏置电流引起的信号频偏小。
