Geometric phase accumulation-based effects in the quantum dynamics of an anisotropically trapped ion

Collectivity, Phase Transitions and Exceptional Points in Open Quantum Systems

Phase transitions in open quantum systems, which are associated with the formation of collective states of a large width and of trapped states with rather small widths, are related to exceptional points of the Hamiltonian. Exceptional points are the singularities of the spectrum and eigenfunctions, when they are considered as functions of a coupling parameter. In the present paper this parameter is the coupling strength to the continuum. It is shown that the positions of the exceptional points (their accumulation point in the thermodynamical limit) depend on the particular type and energy depe…

同时利用量子纠缠与压缩实现亚SQL电场传感

Sub-SQL electronic field sensing by simultaneously using quantum entanglements and squeezings

针对囚禁离子电场传感中单独用量子纠缠或压缩突破SQL增益有限的问题，提出同时利用自旋-振子态纠缠与振子压缩放大累积相位的方案，可有效提升灵敏度增益，为电场传感及其他计量应用突破SQL提供新途径。

利用1+2维动力学解耦技术实现宽量程量子增强旋转传感

Wide-range quantum enhanced rotation sensing with 1+2 dimensional dynamical decoupling techniques

本文提出利用π相位移动序列实现运动动力学解耦，在1+2维混合原子Sagnac干涉仪中显著提升自旋相干时间，从而同时增强旋转传感的灵敏度与动态范围，为高精度惯性导航提供新途径。

Quantum electrodynamics near anisotropic polarizable materials: Casimir-Polder shifts near multi-layers of graphene

In a recent paper we have formulated a theory of non-relativistic quantum electrodynamics in the presence of an inhomogeneous Huttner-Barnett dielectric. Here we generalize the formalism to anisotropic materials and show how it may be modified to include conducting surfaces. We start with the derivation of the photon propagator for a slab of material and use it to work out the energy-level shift near a medium whose conductivity in the direction parallel to the surface far exceeds that in the direction perpendicular to the surface. We investigate the influence of the anisotropy of the material'…

面向QCCD架构的、具有低运动激发的X结快速连续离子输运

Fast continuous ion transport through X-junctions with low motional excitation for QCCD architectures

本文针对QCCD架构的X结输运难题，开发了LHX-T波形设计方法，实现了5μs内90°转弯的低激发高速输运，缩短了QCCD执行周期并降低了输运耗时占比。

Chaos-driven dynamics in spin-orbit coupled atomic gases

The dynamics, appearing after a quantum quench, of a trapped, spin-orbit coupled, dilute atomic gas is studied. The characteristics of the evolution is greatly influenced by the symmetries of the system, and we especially compare evolution for an isotropic Rashba coupling and for an anisotropic spin-orbit coupling. As we make the spin-orbit coupling anisotropic, we break the rotational symmetry and the underlying classical model becomes chaotic; the quantum dynamics is affected accordingly. Within experimentally relevant time-scales and parameters, the system thermalizes in a quantum sense. Th…

Quantum to Classical Transition in a Single-Ion Laser

Stimulated emission of photons from a large number of atoms into the mode of a strong light field is the principle mechanism for lasing in "classical" lasers. The onset of lasing is marked by a threshold which can be characterised by a sharp increase in photon flux as a function of external pumping strength. The same is not necessarily true for the fundamental building block of a laser: a single trapped atom interacting with a single optical radiation mode. It has been shown that such a "quantum" laser can exhibit thresholdless lasing in the regime of strong coupling between atom and radiation…

Phase-Shift Plateaus in the Sagnac Effect for Matter Waves

We simulate ultracold Sagnac atom interferometers using quantum-mechanical matter wavepackets, e.g. Bose-Einstein condensates, that counter-propagate within a rotating ring-trap. We find that the accumulation of the relative phase difference between wavepackets, i.e. the matter wave Sagnac effect, is manifested as discrete phase jumps. These plateaus result from three effects; that the atoms should be initially trapped at rest with respect to the rotating frame, that they counter-propagate with the same group velocities in the rotating frame, and that the imaging is performed in the rotating f…

高效资源的Hadamard测试定制变分框架用于量子计算机上的非线性动力学

Resource-Efficient Hadamard Test Tailored Variational Framework for Nonlinear Dynamics on Quantum Computers

本研究提出了一种低深度的Hadamard测试定制变分框架，用于在量子计算机上高效模拟非线性动力学，并展示了其在湍流模拟中的有效性。

Cyclone：设计高效且高度并行的量子容错存储器QCCD架构协同设计

Cyclone: Designing Efficient and Highly Parallel QCCD Architectural Codesigns for Fault Tolerant Quantum Memory

Cyclone通过环形拓扑结构和同步辅助量子比特，实现高效并行的量子容错存储器设计，显著提升执行速度和代码性能。

通过刘维尔肤效应的光泵浦

Optical pumping through the Liouvillian skin effect

本文揭示了光泵浦过程与刘维尔肤效应之间的内在联系，通过分析态空间中边界条件对刘维尔谱的影响，提出通过设计开放边界条件下的刘维尔能隙来优化光泵浦方案，并展示了引入反直觉耗散通道可显著提升囚禁离子边带冷却效率。