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Off equilibrium dynamics in disordered quantum spin chain

Stéphane Abriet·Dragi Karevski
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Abstract

We study the non-equilibrium time evolution of the average transverse magnetisation and end-to-end correlation functions of the random Ising quantum chain. Starting with fully magnetised states, either in the $x$ or $z$ direction, we compute numerically the average quantities. They show similar behaviour to the homogeneous chain, that is an algebraic decay in time toward a stationary state. During the time evolution, the spatial correlations, measured from one end to the other of the chain, are building up and finally at long time they reach a size-dependent constant depending on the distance from criticality. Analytical arguments are given which support the numerical results.

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Stéphane Abriet, Dragi Karevski. 2002-09-20. Off equilibrium dynamics in disordered quantum spin chain. https://doi.org/10.1140/epjb%2Fe2002-00333-4

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