Related papers: Approximating the long time average of the density operator: Diagonal ensemble

Approximating the long time average of the density operator: Diagonal ensemble

URL: http://arxiv.org/abs/2011.01257v1
Date: Mon, 2 Nov 2020 19:02:04 GMT
Title: Approximating the long time average of the density operator: Diagonal ensemble
Authors: Asl{\i} \c{C}akan, J. Ignacio Cirac, Mari Carmen Ba\~nuls
Abstract summary: We present a method to approximate the diagonal ensemble using tensor networks. We analyze the performance of the method on a non-integrable spin chain.
Score: 0.7734726150561088
License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Abstract: For an isolated generic quantum system out of equilibrium, the long time average of observables is given by the diagonal ensemble, i.e. the mixed state with the same probability for energy eigenstates as the initial state but without coherences between different energies. In this work we present a method to approximate the diagonal ensemble using tensor networks. Instead of simulating the real time evolution, we adapt a filtering scheme introduced earlier in [Phys. Rev. B 101, 144305 (2020)] to this problem. We analyze the performance of the method on a non-integrable spin chain, for which we observe that local observables converge towards thermal values polynomially with the inverse width of the filter.

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