发表机构
School of Physics and Materials Science, Tianjin Normal University; Interdisciplinary center, Tianjin Normal University（天津师范大学物理与材料科学学院; 天津师范大学交叉学科中心）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究通过相干边界链接调控非互易开放量子系统的Liouvillian能隙，揭示粒子数-相干反馈机制，并提供解析与数值验证。
AI 中文摘要
我们研究了一个单粒子Lindblad晶格，其中非互易非相干跳跃与可调谐的相干边界链接相结合。该链接改变了哈密顿量的边界条件，同时保持非相干跳跃速率固定，因此它不直接改变对角粒子数生成器。其对Liouvillian能隙的影响来自粒子数-相干-粒子数反馈：哈密顿量将粒子数耦合到阻尼相干项，消除这些相干项会产生频率依赖的自能，作用于慢粒子数分支。对于周期性参考系统，其中平移对称性同时施加于哈密顿量和耗散子，我们推导出精确的固定动量约化、粒子数连接分支的标量久期方程，以及相关的流体动力学漂移和相干修正扩散。对于开放有限晶格，精确对角化和稀疏近零本征求解器表明，相干边界链接可以在一维中增强或抑制能隙，并在二维中产生几何依赖的响应。我们还表明，当能隙族在所选微扰和可观测量中具有弱可见性时，观测到的弛豫尺度可能不同于$1/\Delta_{\mathcal L}$。周期性构造提供了精确的解析基准，而一维和二维的有限尺寸模拟则展示了相同的相干介导机制如何控制开放边界能隙和可观测弛豫。
英文摘要
We study a single-particle Lindblad lattice in which nonreciprocal incoherent hopping is combined with a tunable coherent boundary link. The link changes the Hamiltonian boundary condition while the incoherent jump rates are kept fixed, so it does not directly alter the diagonal population generator. Its effect on the Liouvillian gap comes from population-coherence-population feedback: the Hamiltonian couples populations to damped coherences, and eliminating those coherences produces a frequency-dependent self-energy for the slow population branch. For the periodic reference system, where translation symmetry is imposed on both the Hamiltonian and the dissipator, we derive an exact fixed-momentum reduction, a scalar secular equation for the population-connected branch, and the associated hydrodynamic drift and coherence-corrected diffusion. For open finite lattices, exact diagonalization and sparse near-zero eigensolvers show that the coherent boundary link can enhance or suppress the gap in one dimension and produce geometry-dependent responses in two dimensions. We also show that an observed relaxation scale can differ from $1/Δ_{\mathcal L}$ when the gap family has weak visibility in the chosen perturbation and observable. The periodic construction gives exact analytical benchmarks, while finite-size simulations in one and two dimensions demonstrate how the same coherence-mediated mechanism controls open-boundary gaps and observable relaxation.
Comments17 pages, 5 figures
