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arXiv · 2207.11849

Landau-Zener transition with energy-dependent decay rate of the excited state

M. E. Raikh
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Abstract

A remarkable feature of the Landau-Zener transition is insensitivity of the survival probability to the decay rate, of the excited state. Namely, the probability for a particle, which is initially in the ground state, to remain in the same state is insensitive to decay, which is due to e.g. coupling to continuum [V. M. Akulin and W. P. Schleich, Phys. Rev. A 46, 4110 (1992)]. This insensitivity was demonstrated for the case when the density of states in the continuum is energy-independent. We study the opposite limit when the density of states in the continuum is a step-like function of energy. As a result of this step-like behavior of the density of states, the decay rate of a driven excited level experiences a jump as a function of time at certain moment t_0. We take advantage of the fact that the analytical solution at t t_0 is known. We show that the decay enters the survival probability when t_0 is comparable to the transition time.

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M. E. Raikh. 2022-07-24. Landau-Zener transition with energy-dependent decay rate of the excited state. https://doi.org/10.1016/j.ssc.2022.114964

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