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arXiv · 1212.6163

Computing complexity measures for quantum states based on exponential families

Sönke Niekamp·Tobias Galla·Matthias Kleinmann·Otfried Gühne
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Abstract

Given a multiparticle quantum state, one may ask whether it can be represented as a thermal state of some Hamiltonian with k-particle interactions only. The distance from the exponential family defined by these thermal states can be considered as a measure of complexity of a given state. We investigate the resulting optimization problem and show how symmetries can be exploited to simplify the task of finding the nearest thermal state in a given exponential family. We also present an algorithm for the computation of the complexity measure and consider specific examples to demonstrate its applicability.

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Sönke Niekamp, Tobias Galla, Matthias Kleinmann, Otfried Gühne. 2012-12-26. Computing complexity measures for quantum states based on exponential families. https://doi.org/10.1088/1751-8113%2F46%2F12%2F125301

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