论文标题
奇怪的量子浴之间的能量运输
Energy Transport between Strange Quantum Baths
论文作者
论文摘要
量子多体系统中具有良好定义的准颗粒的能量运输最近引起了不同场地的兴趣，包括均衡保形场理论，一维量子晶格模型和全息物质。在这里，我们研究了\ emph {奇怪的量子浴}之间没有准颗粒的\ emph {奇怪的量子浴室}，这是由两个sachdev-ye-kitaev（Syk）模型在温度下制成的$ t_l \ neq t_r $，并由费米 - 液体系统连接。我们获得了非平衡能电流的精确表达式，该表达式在大浴缸和系统尺寸的极限以及任何系统浴耦合$ v $中有效。我们表明，Syk Baths的特殊关键性对导热电导有直接的后果，该导热电导高于温度$ t^*（v）\ sim v^4 $，相对于与Quasiparticles系统中预期的线性 - $ t $行为相对于线性 - $ t $行为。有趣的是，$ t^*（v）$恢复线性导电行为，但运输不是由于准颗粒引起的。相反，该系统被奇怪的浴缸重新统治，并变成非弗米液体和最大混乱。最后，我们讨论了完整的非平衡能量电流，并表明其形式与结构$ \ MATHCAL {J} =φ（t_l）-φ（T_R）$兼容，其中$φ（t）\ sim t^γ$和功率定律从$γ= 3/2 $ to $γ= 2 $ dower $ to $ T^$ to $γ= 2 $ t^*$。
Energy transport in quantum many-body systems with well defined quasiparticles has recently attracted interest across different fields, including out of equilibrium conformal field theories, one dimensional quantum lattice models and holographic matter. Here we study energy transport between \emph{strange quantum baths} without quasiparticles, made by two Sachdev-Ye-Kitaev (SYK) models at temperatures $T_L\neq T_R$ and connected by a Fermi-Liquid system. We obtain an exact expression for the nonequilibrium energy current, valid in the limit of large bath and system size and for any system-bath coupling $V$. We show that the peculiar criticality of the SYK baths has direct consequences on the thermal conductance, which above a temperature $T^*(V)\sim V^4$ is parametrically enhanced with respect to the linear-$T$ behavior expected in systems with quasiparticles. Interestingly, below $T^*(V)$ the linear thermal conductance behavior is restored, yet transport is not due to quasiparticles. Rather the system gets strongly renormalized by the strange bath and becomes Non-Fermi-Liquid and maximally chaotic. Finally, we discuss the full nonequilibrium energy current and show that its form is compatible with the structure $\mathcal{J}=Φ(T_L)-Φ(T_R)$, with $Φ(T)\sim T^γ$ and power law crossing over from $γ=3/2$ to $γ=2$ below $T^*$.
