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arXiv · 0905.4934

Quantum decay into a non-flat continuum

James Aisenberg·Itamar Sela·Tsampikos Kottos·Doron Cohen·Alex Elgart
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Abstract

We study the decay of a prepared state into non-flat continuum. We find that the survival probability $P(t)$ might exhibit either stretched-exponential or power-law decay, depending on non-universal features of the model. Still there is a universal characteristic time $t_0$ that does not depend on the functional form. It is only for a flat continuum that we get a robust exponential decay that is insensitive to the nature of the intra-continuum couplings. The analysis highlights the co-existence of perturbative and non-perturbative features in the local density of states, and the non-linear dependence of $1/t_0$ on the strength of the coupling.

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James Aisenberg, Itamar Sela, Tsampikos Kottos, Doron Cohen, Alex Elgart. 2009-05-29. Quantum decay into a non-flat continuum. https://doi.org/10.1088/1751-8113/43/9/095301

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