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arXiv · 1705.00617

Solvable Markovian dynamics of lattice quantum spin models

D. Mesterházy·F. Hebenstreit
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Abstract

We address the real-time dynamics of lattice quantum spin models coupled to single or multiple Markovian dissipative reservoirs using the method of closed hierarchies of correlation functions. This approach allows us to solve a number of quantum spin models exactly in arbitrary dimensions, which is illustrated explicitly with two examples of driven-dissipative systems. We investigate their respective nonequilibrium steady states as well as the full real-time evolution on unprecedented system sizes. Characteristic time scales are derived analytically, which allows us to understand the nontrivial finite-size scaling of the dissipative gap. The corresponding scaling exponents are confirmed by solving numerically for the full real-time evolution of two-point correlation functions.

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D. Mesterházy, F. Hebenstreit. 2017-08-02. Solvable Markovian dynamics of lattice quantum spin models. https://doi.org/10.1103/physreva.96.010104

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