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arXiv · 1502.05175

Engineering adiabaticity at an avoided crossing with optimal control

T. Chasseur·L. S. Theis·Y. R. Sanders·D. J. Egger·F. K. Wilhelm
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Abstract

We investigate ways to optimize adiabaticity and diabaticity in the Landau-Zener model with non-uniform sweeps. We show how diabaticity can be engineered with a pulse consisting of a linear sweep augmented by an oscillating term. We show that the oscillation leads to jumps in populations whose value can be accurately modeled using a model of multiple, photon-assisted Landau-Zener transitions, which generalizes work by Wubs et al. [New J. Phys. 7, 218 (2005)]. We extend the study on diabaticity using methods derived from optimal control. We also show how to preserve adiabaticity with optimal pulses at limited time, finding a non-uniform quantum speed limit.

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T. Chasseur, L. S. Theis, Y. R. Sanders, D. J. Egger, F. K. Wilhelm. 2015-02-24. Engineering adiabaticity at an avoided crossing with optimal control. https://doi.org/10.1103/physreva.91.043421

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