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arXiv · 0810.4845

Relaxation of antiferromagnetic order in spin-1/2 chains following a quantum quench

Peter Barmettler·Matthias Punk·Vladimir Gritsev·Eugene Demler·Ehud Altman
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Abstract

We study the unitary time evolution of antiferromagnetic order in anisotropic Heisenberg chains that are initially prepared in a pure quantum state far from equilibrium. Our analysis indicates that the antiferromagnetic order imprinted in the initial state vanishes exponentially. Depending on the anisotropy parameter, oscillatory or non-oscillatory relaxation dynamics is observed. Furthermore, the corresponding relaxation time exhibits a at the critical point, in contrast to the usual notion of critical slowing down, from which a maximum is expected.

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Peter Barmettler, Matthias Punk, Vladimir Gritsev, Eugene Demler, Ehud Altman. 2009-04-07. Relaxation of antiferromagnetic order in spin-1/2 chains following a quantum quench. https://doi.org/10.1103/physrevlett.102.130603

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