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arXiv · 1909.01398

Probing thermalization through spectral analysis with matrix product operators

Yilun Yang·Sofyan Iblisdir·J. Ignacio Cirac·Mari Carmen Bañuls
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Abstract

We combine matrix product operator techniques with Chebyshev polynomial expansions and present a method that is able to explore spectral properties of quantum many-body Hamiltonians. In particular, we show how this method can be used to probe thermalization of large spin chains without explicitly simulating their time evolution, as well as to compute full and local densities of states. The performance is illustrated with the examples of the Ising and PXP spin chains. For the non-integrable Ising chain, our findings corroborate the presence of thermalization for several initial states, well beyond what direct time-dependent simulations have been able to achieve so far.

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Yilun Yang, Sofyan Iblisdir, J. Ignacio Cirac, Mari Carmen Bañuls. 2019-09-03. Probing thermalization through spectral analysis with matrix product operators. https://doi.org/10.1103/physrevlett.124.100602

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