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We present a theoretical investigation on the propagation of surface waves on the relativistic quantum plasma half-space. The dispersion relations of surface plasmon polaritons (SPPs) and electrostatic surface waves containing relativistic quantum corrected terms are derived. Results show that the frequency of SPPs has a blue-shift, and surface Langmuir oscillations can propagate on the cold plasma half-space due to quantum effects. Numerical evaluation indicates that quantum effects to SPPs and electrostatic surface waves are significant and observable. 相似文献
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Charlene Ng Svetlana Dligatch Hiroshi Amekura Timothy J. Davis Daniel E. Gmez 《Advanced Optical Materials》2015,3(11):1582-1590
One key process in plasmon‐enhanced photocatalysis is the transfer of hot charge–carriers from metal nanostructures into photocatalytically active materials. This process is secondary to the initial step of light absorption by the metal nanostructures. Light absorption in these structures can be controlled by designing complex geometries with tailored optical cross‐sections. Here, a study on one of the simplest nanostructures exhibiting plasmon resonances is presented: 1D gratings of metal wires. Results on the effect of the periodicity of these arrays are presented on the resonant absorption of light and on the hot charge–carrier transfer to a supporting TiO2 thin film. This charge transfer process is monitored by following the photocatalytic decomposition of small organic molecules in solution. Strong enhancements in the rate of decomposition are found that exhibit a correlation with the measured optical extinction spectra of the plasmonic nanostructures. 相似文献
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采用边界元方法研究了快电子在金属纳米双线中激发间隙表面等离激元(SPP)的性质,比较了在不同横截面形状(包括圆形、尖劈形和不规则形状)下电子所激发SPP的不同.研究表明:在以上波导结构中,快电子都能激发具有较长传播距离和较好局域性的低阶单级-单级耦合的间隙等离激元模式;同时通过对波导无量纲价值参数的比较,发现快电子在纳米双线中激发间隙等离激元对双线波导的横截面形状要求不高,横截面形状真正影响的是高阶等离激元模式的激发,而且快电子在截面形状为尖劈的双线波导中能激发局域性更强的间隙SPP.该研究将对实验中利用关键词：表面等离激元间隙模式金属纳米波导 相似文献
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We study the interactions among phonons and the phonon lifetime in a pair‐condensed Fermi gas in the BEC‐BCS crossover in the collisionless regime. To compute the phonon‐phonon coupling amplitudes we use a microscopic model based on a generalized BCS Ansatz including moving pairs, which allows for a systematic expansion around the mean field BCS approximation of the ground state. We show that the quantum hydrodynamic expression of the amplitudes obtained by Landau and Khalatnikov apply only on the energy shell, that is for resonant processes that conserve energy. The microscopic model yields the same excitation spectrum as the Random Phase Approximation, with a linear (phononic) start and a concavity at low wave number that changes from upwards to downwards in the BEC‐BCS crossover. When the concavity of the dispersion relation is upwards at low wave number, the leading damping mechanism at low temperature is the Beliaev‐Landau process 2 phonons ? 1 phonon while, when the concavity is downwards, it is the Landau‐Khalatnikov process 2 phonons ? 2 phonons. In both cases, by rescaling the wave vectors to absorb the dependence on the interaction strength, we obtain a universal formula for the damping rate. This universal formula corrects and extends the original analytic results of Landau and Khalatnikov [ZhETF 19 , 637 (1949)] for the 2?2 processes in the downward concavity case. In the upward concavity case, for the Beliaev 1? 2 process for the unitary gas at zero temperature, we calculate the damping rate of an excitation with wave number q including the first correction proportional to q 7 to the q 5 hydrodynamic prediction, which was never done before in a systematic way. 相似文献
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Polar dielectrics are important optical materials enabling the subwavelength manipulation of light in infrared due to their capability to excite phonon polaritons.In practice,it is highly desired to actively modify these hyperbolic phonon polaritons(HPPs) to optimize or tune the response of the device.In this work,we investigate the plasmonic material,a monolayer graphene,and study its hybrid structure with three kinds of hyperbolic thin films grown on SiO_2 substrate.The inter-mode hybridization and their tunability have been thoroughly clarified from both the band dispersions and the mode patterns numerically calculated through a transfer matrix method.Our results show that these hybrid multilayer structures are of strong potentials for applications in plasmonic waveguides,modulators and detectors in infrared. 相似文献
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The principle of surface wave plasma discharge in a rectangularcavity is introduced simply based on surface plasmon polaritontheory. The distribution of surface-wave electric field at theinterface of the plasma-dielectric slab is investigated by using thethree-dimensional finite-difference time-domain method (3D-FDTD)with different slot-antenna structures. And the experimental imageof discharge with a novel slot antenna array and the simulation ofthe electric field with this slot antenna array are both displayed.Combined with the distribution of surface wave excitation andexperimental results, the numerical simulation performed by using3D-FDTD is shown to be a useful tool in the computer-aided antennadesign for large area planar-type surface-wave plasma sources. 相似文献
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基于金属-电介质-金属波导结构, 提出了一种含双侧多支节型等离子波导滤波器, 采用有限元法研究了其透射特性. 在该结构的透射谱中观察到了基于电磁诱导透明效应的四个窄带透射峰, 并通过模场分布有效阐释了透射谱线中峰值、谷值的产生的物理机理. 数值研究同时表明当每个支节长度线性增加时, 透射峰中心波长也将线性增加. 这一结果可用于指导可调谐、多通道窄带滤波器的设计. 相似文献
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V. I. Silin S. A. Voronov V. A. Yakovlev G. N. Zhizhin 《International Journal of Infrared and Millimeter Waves》1989,10(1):101-120
New experimental evidence is presented which shows that the reliability and the precision of the determination of the optical constants of the metallic and dielectric surfaces can be improved by using the surface electromagnetic wave absorption spectroscopy and SEW phase spectroscopy simultaneously. 相似文献
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为了揭示含支节金属-介质-金属(MIM)型表面等离激元(SPPs)波导透射率谱线的形成机理, 提升基于MIM波导支节结构的微纳光学器件结构设计与性能仿真的效率, 利用MIM波导与微波传输线之间导模特征的相似性, 基于菲涅耳反射公式提出MIM波导支节的修正传输线计算模型。该模型能够有效地计算SPP波在MIM波导支节末端反射产生的附加相位延迟, 从而更加精确地计算MIM波导侧向连接的支节腔对主波导中SPPs模式透射率的调制作用。采用修正传输线模型计算MIM波导侧向耦合单、双支节腔的透射率谱曲线, 并与有限元仿真结果进行对比。结果显示该修正解析模型与经典传输线模型相比, 在预测透射率极小值波长位置方面拥有更高的精度; 同时与数值仿真过程相比, 该模型又具有更高的计算效率。 相似文献
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Cheng Xiao Zhibin Chen Mengze Qin Dongxiao Zhang Hao Wu 《Journal of Raman spectroscopy : JRS》2019,50(3):306-313
A reproducible surface-enhanced Raman scattering (SERS) substrate based on two dimensional (2D) sinusoidal Ag nanograting is presented. This SERS substrate with large area can be easily fabricated by maskless laser interference photolithography. The potential SERS polarization-independent performance of 2D sinusoidal Ag nanograting is deduced by finite difference time domain and demonstrated by SERS detection experiments. A double-enhanced Raman scattering (DERS) substrate by coupling 2D sinusoidal Ag nanograting with Au nanospheres colloids is created. With the optimal DERS substrate, SERS enhancement factor can be 10 orders of magnitude as possible. The DERS substrate was fabricated and an extra SERS effect was proved by experiments. This DERS substrate will be fabricated in a microfluidics-based sensor in the next work and used for in situ, real-time, continuous monitoring of trace water soluble gas-phase or airborne agents, such as trace explosives in air. 相似文献
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The longitudinal response functions are used to generalize the dispersion properties of electron acoustic waves (EAWs) in the presence of quantum recoil, for isotropic, non‐relativistic, degenerate/non‐degenerate plasmas. In order to study the EAWs, the constituents of non‐degenerate (thermal) plasma are considered to be of two groups of electrons having different number density and temperature, namely the cold electrons and the hot electrons. Similarly in degenerate (Fermi) plasma the two population of electrons are considered to be the thinly populated and the thickly populated electrons. The sparsely populated electrons are termed as cold electrons while the densely populated ones are termed as hot electrons. The ions are stationary which form the neutralizing background. The absorption coefficients for Landau damping with the inclusion of the quantum recoil in both plasmas are calculated and discussed. The results are discussed in the context of laser‐produced plasma. 相似文献
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Remote excitation and remote detection of a single quantum dot using propagating surface plasmons on silver nanowire 
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下载免费PDF全文 Using propagating surface plasmons(SPs) on a silver nanowire(NW), we demonstrate that a focused laser light at the end of the silver NW can excite a single quantum dot(QD) microns away from the excitation spot. The QD–NW interaction allows the excited QD convert part of its energy into propagating SPs, which then can be detected at remote sites.Simultaneous multi-QD remote excitation and remote detection can also be realized. Furthermore, the tight confinement of the propagating SPs around the NW surface enables the selective excitation of QDs very close in space, which cannot be realized under the conventional excitation condition. This remote excitation and remote detection approach may find applications in optical imaging and the sensing of chemical and biological systems. 相似文献
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《Advanced Optical Materials》2018,6(15)
Due to their ability to strongly modify the local optical field through the excitation of surface plasmon polaritons (SPPs), plasmonic nanostructures are often used to reshape the emission direction and enhance the radiative decay rate of quantum emitters, such as semiconductor quantum dots (QDs). These features are essential for quantum information processing, nanoscale photonic circuitry, and optoelectronics. However, the modification and enhancement demonstrated thus far have typically led to drastic alterations of the local energy density of the emitters, and hence their intrinsic optical properties, leaving little room for active control. Here, dynamic tuning of the energy states of a single semiconductor QD is demonstrated by optically modifying its local dielectric environment with a nearby plasmonic structure, instead of directly coupling it to the QD. This technique leaves intact the intrinsic optical properties of the QD, while enabling a reversible all‐optical control mechanism that operates below the diffraction limit at low power levels. 相似文献
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Hiroaki Matsui Ya‐Lun Ho Teruo Kanki Hidekazu Tanaka Jean‐Jacques Delaunay Hitoshi Tabata 《Advanced Optical Materials》2015,3(12):1759-1767
Plasmon resonances on 2D nanosquare arrays and their temperature‐dependent modulations are demonstrated using the insulator‐to‐metal transition (IMT) of VO2. A comparison between observed experimental trends and electromagnetic simulations reveals that the plasmon coupling is effective in the periodic 2D alignment of metallic VO2 nanosquares and results in a collective plasmon excitation. This plasmon excitation affects the optical responses of VO2 nanosquares in the mid‐infrared (IR) range through reduction of plasmon damping in relation to the specific band structure of VO2. This preliminary understanding is important for the elucidation of temperature‐dependent plasmon resonances. The IMT of VO2 produces temperature‐dependent plasmon resonances with respect to spectral features. The electrodynamic simulations reveal that these phenomena are based on plasmon coupling in the nanosquare array when each nanosquare acts as a single metallic domain. The hysteretic plasmon resonances are derived from resonant coupling between metallic VO2 nanosquares via the IMT nature of VO2, which results in temperature‐dependent changes in collective plasmon excitations in the nanosquare array. 相似文献
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Alexander E. Minovich Angela E. Klein Dragomir N. Neshev Thomas Pertsch Yuri S. Kivshar Demetrios N. Christodoulides 《Laser u0026amp; Photonics Reviews》2014,8(2):221-232
Airy beams represent an important class of non‐diffracting waves which can be realized on a flat surface. Being generated in the form of surface‐plasmon polaritons, such Airy plasmons demonstrate many remarkable properties: they do not diffract while propagating along parabolic trajectories, and they recover their shape after passing through obstacles. This paper reviews the basic physics of Airy plasmons in both paraxial and non‐paraxial cases, and describes the experimental methods for generation of Airy surface waves on metal surfaces, including a control of their trajectories, as well as the interference of Airy plasmons and hot‐spot generation. Many unusual properties of Airy plasmons can be utilized for useful applications, including plasmonic circuitry and surface tweezers. Picture: Observation of two colliding Airy plasmons. 相似文献
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In this Letter the evolution of a single photon and collective effect of a photon system in background plasma waves are uniformly described in the framework of photon dynamics. In a small-amplitude plasma wave the modulation of photon dynamical behavior by the plasma wave can be treated as perturbation, and photon acceleration effect and photon Landau damping are investigated in linear theory. In an arbitrary-amplitude plasma wave, photon evolution trajectories in phase space are obtained by solving dynamical equations, and photon trapping effect and motion equations in the given plasma wave are also discussed. 相似文献