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arXiv · 1506.07179

Efficient variational diagonalization of fully many-body localized Hamiltonians

Frank Pollmann·Vedika Khemani·J. Ignacio Cirac·S. L. Sondhi
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Abstract

We introduce a unitary matrix-product operator (UMPO) based variational method that approximately finds all the eigenstates of fully many-body localized (fMBL) one-dimensional Hamiltonians. The computational cost of the variational optimization scales linearly with system size for a fixed bond dimension of the UMPO ansatz. We demonstrate the usefulness of our approach by considering the Heisenberg chain in a strongly disordered magnetic field for which we compare the approximation to exact diagonalization results.

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Frank Pollmann, Vedika Khemani, J. Ignacio Cirac, S. L. Sondhi. 2015-06-23. Efficient variational diagonalization of fully many-body localized Hamiltonians. https://doi.org/10.1103/physrevb.94.041116

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