Phase Properties of Photon-Added Coherent States for Nonharmonic Oscillators in a Nonlinear Kerr Medium

The potential of nonharmonic systems has several applications in the field of quantum physics. The photonadded coherent states for annharmonic oscillators in a nonlinear Kerr medium can be used to describe some quantum systems. In this paper, the phase properties of these states including number-phase Wigner distribution function,Pegg-Barnett phase distribution function, number-phase squeezing and number-phase entropic uncertainty relations are investigated. It is found that these states can be considered as the nonclassical states.     

Magneto-optical Kerr effect enhancement at the Wood's anomaly in magnetoplasmonic crystals

Magneto-optical Kerr effect enhancement in longitudinal and transversal configurations is systematically studied in one- and two-dimensional magnetoplasmonic crystals based on the nanostructured nickel films. Spectral dependences of magneto-optical effects demonstrate resonant features with the Fano-type lineshape in the spectral vicinity of the Wood's anomaly associated with excitation of surface magnetoplasmons in Voigt and Faraday configurations, respectively.     

超短强激光脉冲在大气传播中的自聚焦行为

通过建立涉及克尔效应和多光子电离效应的非线性数学模型,利用数值方法研究了超短激光脉冲在大气传播中的聚焦行为。结果表明由自聚焦导致的成丝现象具有间断,而不是一种稳态的模式。每次轴上的成丝都会由于光场损耗减弱,但同时由于克尔效应会使离轴区域的能量间断地补充到光轴上。     

Kerr非线性介质中聚焦像散高斯光束的传输特性

当高功率激光通过Kerr非线性介质传输时,Kerr效应会严重影响激光的传输特性.实际应用中常遇到像散光束.迄今为止,像散光束传输特性的研究大都局限于在线性介质中的传输,而在非线性介质中传输的研究较少,且还未涉及像散激光束通过含光学系统的Kerr非线性介质传输变换的研究.本文主要研究Kerr效应对聚焦光束像散特性和焦移特...     

Acousto-Plasmo-Magnonics: Coupling Spin Waves with Hybridized Phonon-Plasmon Waves in a 2D Artificial Magnonic Crystal Deposited on a Plasmonic Material

Coupling between spin waves (SWs) and other waves in nanostructured media has emerged as an important topic of research because of the rich physics and the potential for disruptive technologies. Herein, a new phenomenon is reported in this family involving coupling between SWs and hybridized phonon-plasmon waves in a 2D periodic array of magnetostrictive nanomagnets deposited on a silicon substrate with an intervening thin film of aluminium that acts as a source of surface plasmons. Hybridized phonon-plasmon waves naturally form in this composite material when exposed to ultrashort laser pulses and they non-linearly couple with SWs to produce a new breed of waves – acousto-plasmo-spin waves that can exhibit a “frequency comb” spanning more than one octave. This phenomenon, that we call acousto-plasmo-magnonics resulting from tripartite coupling of magnons, phonons and plasmons, is studied with time-resolved magneto-optical-Kerr-effect microscopy. The findings also reveal the presence of parametric amplification in this system; energy is transferred from the hybridized phonon-plasmon modes to the acousto-plasmo-spin wave modes to amplify the latter. This opens a path to design novel active metamaterials with tailored and enhanced response. It may enable high-efficiency magneto-mechanical-plasmonic frequency mixing in the GHz−THz frequency regime and provide a unique avenue to study non-linear coupling, parametric amplification, and frequency comb physics.     

Successive approximation-like 4-bit full-optical analog-to-digital converter based on Kerr-like nonlinear photonic crystal ring resonators

Implementing of photonic sampling and quantizing analog-to-digital converters (ADCs) enable us to extract a single binary word from optical signals without need for extra electronic assisting parts. This would enormously increase the sampling and quantizing time as well as decreasing the consumed power. To this end, based on the concept of successive approximation method, a 4-bit full-optical ADC that operates using the intensity-dependent Kerr-like nonlinearity in a two dimensional photonic crystal (2DPhC) platform is proposed. The Silicon (Si) nanocrystal is chosen because of the suitable nonlinear material characteristic. An optical limiter is used for the clamping and quantization of each successive levels that represent the ADC bits. In the proposal, an energy efficient optical ADC circuit is implemented by controlling the system parameters such as ring-to-waveguide coupling coefficients, the ring’s nonlinear refractive index, and the ring’s length. The performance of the ADC structure is verified by the simulation using finite difference time domain (FDTD) method.     

Microscopic origin of asymmetric magnetization reversal of Co/Pt multilayers with perpendicular magnetic anisotropy

We have comprehensively investigated asymmetric magnetization reversal behaviors of (x-Å Co/7.7 Å Pt)₅ multilayers (x = 3.1 and 4.7) with perpendicular magnetic anisotropy. Our direct observation of magnetic domain structures by means of magneto-optical microscopy reveals that the asymmetry arises both from nucleation and wall-motion processes. An asymmetric nucleation behavior is observed, which could be originated from the preexisting non-reversed domains which might have a reproducible or random spatial distribution, controllable by tuning the field profile. An asymmetric wall-motion behavior stemming from asymmetric stripe domain evolution is also observed.     

Kerr效应对原子与双模场Raman相互作用模型腔场谱的影响

研究了含Kerr介质高Q腔中单个二能级原子与双模量子化光场发生Raman耦合过程的腔场谱,给出原子初态处于基态而初始光场为数态时的数值结果.发现在一般情况下,两模腔场谱均为双峰结构.Kerr效应对真空场谱结构无影响.在弱场条件下,Kerr效应的增强会导致各模高频峰明显增高,而低频峰明显降低;在强场条件下,各峰峰位都随着Kerr效应增强明显右移,谱结构整体偏离原共振频率.     

Gravitational Waves from a Pseudo-Newtonian Kerr Field with Halos

A close relation between gravitational waveforms and the types of trajectories in a superposed field between a pseudo-Newtonian Kerr black hole and quadrupolar halos is shown in detail. The gravitational waveforms emitted from circular, KAM tori and chaotic orbits must be periodic, quasiperiodic and stochastic, respectively. The chaotic motion can maximally enhance both the amplitudes and the energy emission rates of the waves.     

Kerr介质中光场与V型三能级原子依赖强度耦合相互作用系统的原子偶极压缩

利用全量子理论,研究了Kerr介质中单模光场与V型三能级原子依赖强度耦合的相互作用系统中原子偶极压缩效应,采用数值计算的方法讨论了Kerr介质常数χ和失谐量Ω对原子偶极压缩的影响.结果表明:Kerr效应对原子偶极压缩效应起着不同程度的减弱作用,适当大小的失谐量Ω有利于原子偶极压缩.