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arXiv · 2006.02989

Transfer matrix for long-range potentials

Farhang Loran·Ali Mostafazadeh
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Abstract

We extend the notion of the transfer matrix of potential scattering to a large class of long-range potentials $v(x)$ and derive its basic properties. We outline a dynamical formulation of the time-independent scattering theory for this class of potentials where we identify their transfer matrix with the $S$-matrix of a certain effective non-unitary two-level quantum system. For sufficiently large values of $|x|$, we express $v(x)$ as the sum of a short-range potential and an exactly solvable long-range potential. Using this result and the composition property of the transfer matrix, we outline an approximation scheme for solving the scattering problem for $v(x)$. To demonstrate the effectiveness of this scheme, we construct an exactly solvable long-range potential and compare the exact values of its reflection and transmission coefficients with those we obtain using our approximation scheme.

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Farhang Loran, Ali Mostafazadeh. 2020-06-04. Transfer matrix for long-range potentials. https://doi.org/10.1088/1751-8121%2Fab9c5a

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