论文标题
在landauer-büttiker形式主义中,量子淬火
On Landauer--Büttiker formalism from a quantum quench
论文作者
论文摘要
我们研究受任意局部潜能的自由费米式一维系统中的运输。运输所需的偏差是由最初的高度非平衡分布建模的,其中只有一半的系统被人群。除此之外,当运输启动时,当地潜力也突然改变了。对于这样的淬灭协议,我们计算最初空部分中粒子数的完整计数统计量(FC)。在热力学极限中,FCS可以通过弗雷德尔姆决定因素表示,具体取决于散射数据和淬火前的散射溶液和QUEST溶液。我们讨论获得的决定因素的大渐近行为,并观察到,如果在敌对后电位的光谱中存在两个或多个结合状态,那么有关初始状态的信息将在FCS的持续振荡中表现出来。相反,当没有结合状态时,FC的渐近行为仅取决于淬火后电位的散射数据,而Quench电位的散射数据在当前(第一刻)由Landauer-Büttiker形式主义给出。有关初始状态的信息只能在瞬态动力学中观察到。
We study transport in the free fermionic one-dimensional systems subjected to arbitrary local potentials. The bias needed for the transport is modeled by the initial highly non-equilibrium distribution where only half of the system is populated. Additionally to that, the local potential is also suddenly changed when the transport starts. For such a quench protocol we compute the Full Counting Statistics (FCS) of the number of particles in the initially empty part. In the thermodynamic limit, the FCS can be expressed via the Fredholm determinant with the kernel depending on the scattering data and Jost solutions of the pre-quench and the post-quench potentials. We discuss the large-time asymptotic behavior of the obtained determinant and observe that if two or more bound states are present in the spectrum of the post-quench potential the information about the initial state manifests itself in the persistent oscillations of the FCS. On the contrary, when there are no bound states the asymptotic behavior of the FCS is determined solely by the scattering data of the post-quench potential, which for the current (the first moment) is given by the Landauer--Büttiker formalism. The information about the initial state can be observed only in the transient dynamics.