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Pseudo-time Schroedinger equation with absorbing potential for quantum scattering calculations

A. Neumaier·V. A. Mandelshtam
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Abstract

The Schroedinger equation with an energy-dependent complex absorbing potential, associated with a scattering system, can be reduced for a special choice of the energy-dependence to a harmonic inversion problem of a discrete pseudo-time correlation function. An efficient formula for Green's function matrix elements is also derived. Since the exact propagation up to time 2t can be done with only t real matrix-vector products, this gives an unprecedently efficient scheme for accurate calculations of quantum spectra for possibly very large systems.

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A. Neumaier, V. A. Mandelshtam. 2001-01-05. Pseudo-time Schroedinger equation with absorbing potential for quantum scattering calculations. https://doi.org/10.1103/physrevlett.86.5031

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