Moroder Mattia, Culhane Oisín, Zawadzki Krissia, Goold John
Department of Physics, Arnold Sommerfeld Center for Theoretical Physics (ASC), Munich Center for Quantum Science and Technology (MCQST), <a href="https://ror.org/05591te55">Ludwig-Maximilians-Universität München</a>, 80333 München, Germany.
School of Physics, <a href="https://ror.org/02tyrky19">Trinity College Dublin</a>, Dublin 2, Ireland.
Phys Rev Lett. 2024 Oct 4;133(14):140404. doi: 10.1103/PhysRevLett.133.140404.
We investigate the quantum Mpemba effect from the perspective of nonequilibrium quantum thermodynamics by studying relaxation dynamics of quantum systems coupled to a Markovian heat bath, which are described by Davies maps. Starting from a state with coherences in the energy eigenbasis, we demonstrate that an exponential speedup to equilibrium will always occur if the state is transformed to a diagonal state in the energy eigenbasis, provided that the spectral gap of the generator is defined by a complex eigenvalue. When the transformed state has a higher nonequilibrium free energy, we argue using thermodynamic reasoning that this is a genuine quantum Mpemba effect. Furthermore, we show how a unitary transformation on an initial state can always be constructed to yield the effect and demonstrate our findings by studying the dynamics of both the nonequilibrium free energy and the irreversible entropy production in single and multiqubit examples.
我们从非平衡量子热力学的角度研究量子姆潘巴效应，通过研究与马尔可夫热库耦合的量子系统的弛豫动力学，这些系统由戴维斯映射描述。从能量本征基中有相干性的状态开始，我们证明，如果状态在能量本征基中变换为对角状态，只要生成器的谱隙由复本征值定义，那么向平衡的指数加速将总是会发生。当变换后的状态具有更高的非平衡自由能时，我们用热力学推理认为这是一种真正的量子姆潘巴效应。此外，我们展示了如何总是可以构造一个对初始状态的酉变换来产生这种效应，并通过研究单量子比特和多量子比特示例中的非平衡自由能和不可逆熵产生的动力学来证明我们的发现。
