Department of Physics, FMF, University of Ljubljana, Jadranska 19, 1000 Ljubljana, Slovenia.
Phys Rev Lett. 2014 Feb 14;112(6):067201. doi: 10.1103/PhysRevLett.112.067201. Epub 2014 Feb 10.
We study the full counting statistics for interacting quantum many-body spin systems weakly coupled to the environment. In the leading order in the system-bath coupling, we derive exact spin current statistics for a large class of parity symmetric spin-1/2 systems driven by a pair of Markovian baths with local coupling operators. Interestingly, in this class of systems the leading-order current statistics are universal and do not depend on details of the Hamiltonian. Furthermore, in the specific case of a symmetrically boundary driven anisotropic Heisenberg (XXZ) spin-1/2 chain, we explicitly derive the third-order nonlinear corrections to the current statistics.
我们研究了与环境弱耦合的相互作用量子多体自旋系统的全计数统计。在系统-浴耦合的领先阶次下，我们针对一大类满足宇称守恒的自旋-1/2 系统，推导出了由一对具有局域耦合算符的马尔科夫浴驱动时的精确自旋流统计。有趣的是，在这一类系统中，领先阶次的电流统计是普遍的，不依赖于哈密顿量的细节。此外，在一个对称边界驱动的各向异性海森堡（XXZ）自旋-1/2 链的具体情况下，我们明确推导出了电流统计的三阶非线性修正。
