PT对称复杂晶体中的不可见性

Unidirectional Invisibility and PT-Symmetry with Graphene

We investigate the reflectionlessness and invisibility properties in the transverse electric (TE) mode solution of a linear homogeneous optical system which comprises the $\mathcal{PT}$-symmetric structures covered by graphene sheets. We derive analytic expressions, indicate roles of each parameter governing optical system with graphene and justify that optimal conditions of these parameters give rise to broadband and wide angle invisibility. Presence of graphene turns out to shift the invisible wavelength range and to reduce the required gain amount considerably, based on its chemical potenti…

Reciprocal and unidirectional scattering of parity-time symmetric structures

Parity-time (PT) symmetry is of great interest. The reciprocal and unidirectional features are intriguing besides the PT symmetry phase transition. Recently, the reciprocal transmission, unidirectional reflectionless and invisibility are intensively studied. Here, we show the reciprocal reflection/transmission in PT -symmetric system is closely related to the type of PT symmetry, that is, the axial (reflection) PT symmetry leads to reciprocal reflection (transmission). The results are further elucidated by studying the scattering of rhombic ring form coupled resonators with enclosed synthetic …

An update on coherent scattering from complex non-PT-symmetric Scarf II potential with new analytic forms

The versatile and exactly solvable Scarf II has been predicting, confirming and demonstrating interesting phenomena in complex PT-symmetric sector, most impressively. However, for the non-PT-symmetric sector it has gone underutilized. Here, we present most simple analytic forms for the scattering coefficients $(T(k),R(k),|\det S(k)|)$. On one hand, these forms demonstrate earlier effects and confirm the recent ones. On the other hand they make new predictions - all simply and analytically. We show the possibilities of both self-dual and non-self-dual spectral singularities (NSDSS) in two non-P…

利用光子晶体光纤产生对称可因式分解态光子对

Generation of photon pairs in symmetric factorable state by using photonic crystal fibers

实验研究了一种基于光子晶体光纤的对称可因式分解光子对源。具有几乎相同带宽的闲频光子和信号光子分别以807.5nm和1364.1nm为中心。通过测量泵浦光、信号光和闲频光的光谱与光子对的相关关系，证实了光谱去相关的性质。

基于复合光子晶体对称腔的纳米毛细管光纤腔量子电动力学研究

Cavity quantum electrodynamics on a nanocapillay fiber using a composite photonic crystal symmetric cavity

本研究报道了纳米毛细管光纤上复合光子晶体对称腔的腔量子电动力学条件，通过将单量子发射器置于波腹位置实现87%的最大通道效率，为量子技术中单光子操控应用提供了平台。

超对称产生的单向不可见PT对称光学晶体

Supersymmetry generated one-way invisible PT-symmetric optical crystals

我们使用超对称变换设计透明和单向无反射（因此单向不可见）的复杂晶体与平衡的增益和损耗的档案。散射系数的研究使用传输矩阵法。它表明，从左边的反射量可以任意接近零，而从右边的反射是任意增强（反之亦然）。

Talbot self-imaging in $\mathcal{PT}$-symmetric complex crystals

The Talbot effect, i.e. the self-imaging property of a periodic wave in near-field diffraction, is a remarkable interference phenomenon in paraxial systems with continuous translational invariance. In crystals, i.e. systems with discrete translational invariance, self-imaging has been regarded so far as a seldom effect, restricted to special sets of initial field distributions. Here it is shown that in a class of gapless $\mathcal{PT}$-symmetric complex crystals at the symmetry breaking threshold Talbot revivals can arise for almost any initial periodic wave distribution which is commensurate …

Cavity Control over Heavy-Hole Spin Qubits in Inversion-Symmetric Crystals

The pseudospin of heavy-holes (HHs) confined in a semiconductor quantum dot (QD) represents a promising candidate for a fast and robust qubit. While hole spin manipulation by a classical electric field utilizing the Dresselhaus spin-orbit interaction (SOI) has been demonstrated, our work explores cavity-based qubit manipulation and coupling schemes for inversion-symmetric crystals forming a planar HH QD. Choosing the exemplary material Germanium (Ge), we derive an effective cavity-mediated ground state spin coupling that harnesses the cubic Rashba SOI. In addition, we propose an optimal set of…

A unidirectional invisible PT-symmetric complex crystal with arbitrary thickness

We introduce a new class of $\mathcal{PT}$-symmetric complex crystals which are almost transparent and one-way reflectionless over a broad frequency range around the Bragg frequency, i.e. unidirectionally invisible, regardless of the thickness $L$ of the crystal. The $\mathcal{PT}$-symmetric complex crystal is synthesized by a supersymmetric transformation of an Hermitian square well potential, and exact analytical expressions of transmission and reflection coefficients are given. As $L$ is increased, the transmittance and reflectance from one side remain close to one and zero, respectively, w…

对称子空间外连续时间晶体中的奇异同步

Exotic synchronization in continuous time crystals outside the symmetric subspace

本文研究驱动耗散自旋模型中非对称子空间对连续时间晶体动力学的影响，发现多稳态可引发嵌合体状态、团簇同步、振荡死亡及混沌迹象等奇异非线性现象。

连续时间晶体作为PT对称态与临界异常点的出现

Continuous time crystals as a PT symmetric state and the emergence of critical exceptional points

本文证明Lindbladian PT对称性可普遍产生持续周期振荡，涵盖耗散连续时间晶体模型和空间扩展玻色系统，并揭示PT对称相中的周期轨道为中心型，依赖初始态。