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arXiv · 0706.2539

Many body localization in Heisenberg XXZ magnet in a random field

Marko Znidaric·Tomaz Prosen·Peter Prelovsek
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Abstract

We numerically investigate Heisenberg XXZ spin-1/2 chain in a spatially random static magnetic field. We find that tDMRG simulations of time evolution can be performed efficiently, namely the dimension of matrices needed to efficiently represent the time-evolution increases linearly with time and entanglement entropies for typical chain bipartitions increase logarithmically. As a result, we show that for large enough random fields infinite temperature spin-spin correlation function displays exponential localization in space indicating insulating behavior of the model.

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Marko Znidaric, Tomaz Prosen, Peter Prelovsek. 2008-03-19. Many body localization in Heisenberg XXZ magnet in a random field. https://doi.org/10.1103/physrevb.77.064426

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