arXiv:1201.3341 · Physical Review Letters

Odd-Particle Systems in the Shell Model Monte Carlo Method: Circumventing a Sign Problem

Abhishek Mukherjee, Y. Alhassid

Published Jul 17, 2012• 14 citations

Abstract

The shell model Monte Carlo method is a powerful technique to calculate thermal and ground-state properties of strongly correlated finite-size systems. However, its application to odd-particle-number systems has been hampered by the sign problem that originates from the projection on an odd number of particles. We circumvent this sign problem for the ground-state energy by extracting the ground-state energy of the odd-particle-number system from the asymptotic behavior of the imaginary-time single-particle Green's function of the even-particle-number system. We apply this method to calculate pairing gaps of nuclei in the iron region. Our results are in good agreement with experimental pairing gaps.

DOI: 10.1103/physrevlett.109.032503

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