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arXiv · 2012.11763

Time-rescaling of Dirac dynamics: shortcuts to adiabaticity in ion traps and Weyl semimetals

Agniva Roychowdhury·Sebastian Deffner
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Abstract

Only very recently, rescaling time has been recognized as a way to achieve adiabatic dynamics in fast processes. The advantage of time-rescaling over other shortcuts to adiabaticity is that it does not depend on the eigenspectrum and eigenstates of the Hamiltonian. However, time-rescaling requires that the original dynamics are adiabatic, and in the rescaled time frame the Hamiltonian exhibits non-trivial time-dependence. In this work, we show how time-rescaling can be applied to Dirac dynamics, and we show that all time-dependence can be absorbed into the effective potentials through a judiciously chosen unitary transformation. This is demonstrated for two experimentally relevant scenarios, namely for ion traps and adiabatic creation of Weyl points.

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Agniva Roychowdhury, Sebastian Deffner. 2020-12-22. Time-rescaling of Dirac dynamics: shortcuts to adiabaticity in ion traps and Weyl semimetals. https://doi.org/10.3390/e23010081

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