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arXiv · 1812.04776

Emergent prethermalization signatures in out-of-time ordered correlations

Ken Xuan Wei·Pai Peng·Oles Shtanko·Iman Marvian·Seth Lloyd·Chandrasekhar Ramanathan·Paola Cappellaro
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Abstract

How a many-body quantum system thermalizes --or fails to do so-- under its own interaction is a fundamental yet elusive concept. Here we demonstrate nuclear magnetic resonance observation of the emergence of prethermalization by measuring out-of-time ordered correlations. We exploit Hamiltonian engineering techniques to tune the strength of spin-spin interactions and of a transverse magnetic field in a spin chain system, as well as to invert the Hamiltonian sign to reveal out-of-time ordered correlations. At large fields, we observe an emergent conserved quantity due to prethermalization, which can be revealed by an early saturation of correlations. Our experiment not only demonstrates a new protocol to measure out-of-time ordered correlations, but also provides new insights in the study of quantum thermodynamics.

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Ken Xuan Wei, Pai Peng, Oles Shtanko, Iman Marvian, Seth Lloyd, Chandrasekhar Ramanathan, Paola Cappellaro. 2018-12-12. Emergent prethermalization signatures in out-of-time ordered correlations. https://doi.org/10.1103/physrevlett.123.090605

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