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arXiv · 1807.02360

Operator Noncommutativity and Irreversibility in Quantum Chaos

Ryusuke Hamazaki·Kazuya Fujimoto·Masahito Ueda
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Abstract

We argue that two distinct probes of quantum chaos, i.e., the growth of noncommutativity of two unequal-time operators and the degree of irreversibility in a time-reversal test, are equivalent for initially localized states. We confirm this for interacting nonintegrable many-body systems and a quantum kicked rotor. Our results show that three-point out-of-time-ordered correlators dominate the growth of the squared commutator for initially localized states, in stark contrast to four-point out-of-time-ordered correlators that have extensively been studied for thermal initial states.

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Ryusuke Hamazaki, Kazuya Fujimoto, Masahito Ueda. 2018-07-06. Operator Noncommutativity and Irreversibility in Quantum Chaos. https://arxiv.org/abs/1807.02360

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