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arXiv · 1804.01683

Maximum Quantum Entropy Method

Jae-Hoon Sim·Myung Joon Han
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Abstract

Maximum entropy method for analytic continuation is extended by introducing quantum relative entropy. This new method is formulated in terms of matrix-valued functions and therefore invariant under arbitrary unitary transformation of input matrix. As a result, the continuation of off-diagonal elements becomes straightforward. Without introducing any further ambiguity, the Bayesian probabilistic interpretation is maintained just as in the conventional maximum entropy method. The applications of our generalized formalism to a model spectrum and a real material demonstrate its usefulness and superiority.

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Jae-Hoon Sim, Myung Joon Han. 2018-04-05. Maximum Quantum Entropy Method. https://doi.org/10.1103/physrevb.98.205102

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