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arXiv · 1407.2784

Fermion-dimer scattering using an impurity lattice Monte Carlo approach and the adiabatic projection method

Serdar Elhatisari·Dean Lee
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Abstract

We present lattice Monte Carlo calculations of fermion-dimer scattering in the limit of zero-range interactions using the adiabatic projection method. The adiabatic projection method uses a set of initial cluster states and Euclidean time projection to give a systematically improvable description of the low-lying scattering cluster states in a finite volume. We use Lüscher's finite-volume relations to determine the s-wave, p-wave, and d-wave phase shifts. For comparison, we also compute exact lattice results using Lanczos iteration and continuum results using the Skorniakov-Ter-Martirosian equation. For our Monte Carlo calculations we use a new lattice algorithm called impurity lattice Monte Carlo. This algorithm can be viewed as a hybrid technique which incorporates elements of both worldline and auxiliary-field Monte Carlo simulations.

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Serdar Elhatisari, Dean Lee. 2014-12-01. Fermion-dimer scattering using an impurity lattice Monte Carlo approach and the adiabatic projection method. https://doi.org/10.1103/physrevc.90.064001

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