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arXiv · 2006.01313

Detecting out-of-time-order correlations via quasi-adiabatic echoes as a tool to reveal quantum coherence in equilibrium quantum phase transitions

Robert J. Lewis-Swan·Sean R. Muleady·Ana Maria Rey
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Abstract

We propose a new dynamical method to connect equilibrium quantum phase transitions and quantum coherence using out-of-time-order correlations (OTOCs). Adopting the iconic Lipkin-Meshkov-Glick and transverse-field Ising models as illustrative examples, we show that an abrupt change in coherence and entanglement of the ground state across a quantum phase transition is observable in the spectrum of multiple quantum coherence (MQC) intensities, which are a special type of OTOC. We also develop a robust protocol to obtain the relevant OTOCs using quasi-adiabatic quenches through the ground state phase diagram. Our scheme allows for the detection of OTOCs without time-reversal of coherent dynamics, making it applicable and important for a broad range of current experiments where time-reversal cannot be achieved by inverting the sign of the underlying Hamiltonian.

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Robert J. Lewis-Swan, Sean R. Muleady, Ana Maria Rey. 2020-06-01. Detecting out-of-time-order correlations via quasi-adiabatic echoes as a tool to reveal quantum coherence in equilibrium quantum phase transitions. https://doi.org/10.1103/physrevlett.125.240605

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