Resonant level model coupled to a Sachdev-Ye-Kitaev bath

We investigate the non-equilibrium dynamics of a resonant level model coupled to a strongly interacting electron bath modeled by a Sachdev-Ye-Kitaev (SYK) model. Different from the well-investigated case of a structureless non-interacting Fermi gas bath leading to a temperature-independent exponential decay of the impurity orbital occupation, we find a temperature-dependent oscillatory decay. We attribute this difference to the lack of quasiparticles in the SYK model, which is reflected in its singular density of states at the Fermi level. Our results are exact and can be obtained analytically by mapping to a suitably structured Fermi gas bath as an ancillary model for the SYK bath.本研究针对与以萨赫夫-叶-基塔耶夫（Sachdev-Ye-Kitaev, SYK）模型刻画的强相互作用电子库耦合的共振能级模型的非平衡动力学展开探究。相较于已被充分研究的、由无结构非相互作用费米气体库所导致杂质轨道占据数呈温度无关指数衰减的情形，我们发现该系统呈现出温度依赖的振荡衰减行为。我们将该差异归因于SYK模型中不存在准粒子，这一特性可通过其费米能级处奇异的态密度得以体现。本研究结果为精确解析解，可通过将SYK库映射为适当结构化的费米气体库辅助模型来解析获得。