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arXiv · 2010.04497

Transition time estimation for $δ$-function coupling in two state problem: An analytically solvable model

Mayank Vashistha·Chinmoy Samanta·Aniruddha Chakraborty
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Abstract

We propose a simple method to calculate transition time in a two-state scattering problem, where two constant potentials are coupled by a delta function potential $V_{12}=V_{21}=k_0 δ(x)$. The exact analytical expression for the time of transition $τ$ is derived. We notice $τ$ explicitly depends on the second state's potential energy along with the incident energy and coupling strength. We also observe from the derived expression of $τ$ that depending on the initial energy, the coupling potential could behave like a transparent or opaque medium to the incident wave in a single state equivalent description.

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Mayank Vashistha, Chinmoy Samanta, Aniruddha Chakraborty. 2020-10-09. Transition time estimation for $δ$-function coupling in two state problem: An analytically solvable model. https://doi.org/10.1016/j.cplett.2021.138436

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