Ballistic Spin Transport in a Periodically Driven Integrable Quantum System
Ballistic Spin Transport in a Periodically Driven Integrable Quantum System
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DOI：
10.1103/physrevlett.122.150605
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发表时间：
2019-04-19
影响因子：
8.6
通讯作者：
Prosen, Tomaz
中科院分区：
文献类型：
--
作者：
Ljubotina, Marko;Zadnik, Lenart;Prosen, Tomaz
我们证明了可积么正量子电路的弹道自旋输运，它既可以理解为可积周期驱动(Floquit)自旋链的范例，也可以理解为托特化各向异性(XXZ)Heisenberg自旋1/2模型。我们构造了一个打破自旋-反转对称性的准局域守恒律的解析族，并计算了自旋Drude重量的下界，发现它是各向异性参数的分形函数。对自旋输运的大量数值模拟表明，这个分形界实际上是紧的。
We demonstrate ballistic spin transport of an integrable unitary quantum circuit, which can be understood either as a paradigm of an integrable periodically driven (Floquet) spin chain, or as a Trotterized anisotropic (XXZ) Heisenberg spin-1/2 model. We construct an analytic family of quasilocal conservation laws that break the spin-reversal symmetry and compute a lower bound on the spin Drude weight, which is found to be a fractal function of the anisotropy parameter. Extensive numerical simulations of spin transport suggest that this fractal lower bound is in fact tight.