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arXiv · 2001.11166

Slow oscillating dynamics of a two-level system subject to a fast telegraph noise: beyond the NIBA approximation

V. V. Mkhitaryan·M. E. Raikh
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Abstract

We study the dynamics of a two-site model in which the tunneling amplitude between the sites is not constant but rather a high-frequency noise. Obviously, the population imbalance in this model decays exponentially with time. Remarkably, the decay is modified dramatically when the level asymmetry fluctuates in-phase with fluctuations of the tunneling amplitude. For particular type of these in-phase fluctuations, namely, the telegraph noise, we find the exact solution for the average population dynamics. It appears that the population imbalance between the sites starting from 1 at time $t=0$ approaches a constant value in the limit $t\rightarrow \infty$. At finite bias, the imbalance goes to zero at $t\rightarrow \infty$, while the dynamics of the decay governed by noise acquires an oscillatory character.

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V. V. Mkhitaryan, M. E. Raikh. 2020-01-30. Slow oscillating dynamics of a two-level system subject to a fast telegraph noise: beyond the NIBA approximation. https://doi.org/10.1063/10.0010199

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