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arXiv · 0711.1218

The two-body random spin ensemble and a new type of quantum phase transition

Iztok Pizorn·Tomaz Prosen·Stefan Mossmann·Thomas H. Seligman
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Abstract

We study the properties of a two-body random matrix ensemble for distinguishable spins. We require the ensemble to be invariant under the group of local transformations and analyze a parametrization in terms of the group parameters and the remaining parameters associated with the "entangling" part of the interaction. We then specialize to a spin chain with nearest neighbour interactions and numerically find a new type of quantum phase transition related to the strength of a random external field i.e. the time reversal breaking one body interaction term.

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Iztok Pizorn, Tomaz Prosen, Stefan Mossmann, Thomas H. Seligman. 2007-11-08. The two-body random spin ensemble and a new type of quantum phase transition. https://doi.org/10.1088/1367-2630%2F10%2F2%2F023020

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