Crossing time in the Landau-Zener quantum dynamics in a super Ohmic environment

• URL: http://arxiv.org/abs/2105.03526v1
• Date: Fri, 7 May 2021 22:24:20 GMT
• Title: Crossing time in the Landau-Zener quantum dynamics in a super Ohmic environment
• Authors: Peter Nalbach
• Abstract summary: We study the dynamics of a quantum two state system driven through an avoided crossing. We determine the dynamics and the Landau-Zener probability employing the numerical exact quasi-adiabatic path.
• Score: 0.0
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: We study the dynamics of a quantum two state system driven through an avoided crossing under the influence of a super Ohmic environment, i.e. a longitudinal as well as a transversal one. The crossing time window, in which relaxation influences the dynamics, is centered around the avoided crossing. We determine the dynamics and the Landau-Zener probability employing the numerical exact quasi-adiabatic path integral. At weak coupling we show that the numerically less demanding nonequilibrium Bloch equations provide an accurate description. The crossing time depends strongly not only on the system-bath coupling strength but also on the bath spectral cut-off frequency in contrast to the situation in an Ohmic bath. Our results enable to design quantitative protocols which drive quantum systems out of the influence range of relaxation.

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