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arXiv · 1805.10160

Quantum time mirrors for general two-band systems

Phillipp Reck·Cosimo Gorini·Klaus Richter
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Abstract

Methods that are devised to achieve reversal of quantum dynamics in time have been named "quatum time mirrors". Such a time mirror can be considered as a generalization of Hahn's spin echo to systems with continuous degrees of freedom. We extend the quantum time mirror protocol originally proposed for Dirac dispersions to arbitrary two-band systems and establish the general requirements for its efficient implementation. We further discuss its sensitivity to various non- homogeneous perturbations including disorder potentials and the effect of external static magnetic and electric fields. Our general statements are verified for a number of exemplary Hamiltonians, whose phase-coherent dynamics are studied both analytically and numerically. The Hamiltonians considered can be used to describe the low-energy properties of systems as diverse as cold atom- optics setups, direct band gap semiconductors or (mono- or bilayer) graphene. We discuss the consequences of many-body effects at a qualitative level, and consider the protocol feasibility in state-of-the-art experimental setups.

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Phillipp Reck, Cosimo Gorini, Klaus Richter. 2018-05-25. Quantum time mirrors for general two-band systems. https://doi.org/10.1103/physrevb.98.125421

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