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arXiv · 2109.13647

Nonadiabatic control of quantum transport fidelity in dissipative cold media

Arnab Chakrabarti·Igor Mazets·Tian-Niu Xu·Xi Chen·Gershon Kurizki
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Abstract

We put forth a hitherto unexplored control strategy that enables finite-speed, high-fidelity transport of a quantum wavepacket through a low-temperature dissipative medium. The control consists in confining the wavepacket within a shallow anharmonic trap (tweezer), whose nonuniform velocity is steered so as to maximize the transfer fidelity between two locations. A relevant scenario is a quantum impurity moving through an ultracold gas. Unlike shortcuts to adiabaticity, our approach can simultaneously cope with wavepacket leakage via non-adiabatic and phonon-mediated processes, provided both act perturbatively. Nor does our approach require the application of compensating forces or counter-diabatic fields and thereby avoids the practical shortcomings of shortcut techniques. Instead, optimal (highest fidelity) transport is achieved here by minimizing the functional overlap of the varying velocity-spectrum of the chosen trajectory with the combined (bath-induced and non-adiabatic) leakage spectrum.

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Arnab Chakrabarti, Igor Mazets, Tian-Niu Xu, Xi Chen, Gershon Kurizki. 2021-09-28. Nonadiabatic control of quantum transport fidelity in dissipative cold media. https://arxiv.org/abs/2109.13647

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