Variance minimization variational Monte Carlo method

Imran Khan; Bo Gao

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Variance minimization variational Monte Carlo method

Imran Khan·Bo Gao

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Abstract

We present a variational Monte Carlo (VMC) method that works equally well for the ground and the excited states of a quantum system. The method is based on the minimization of the variance of energy, as opposed to the energy itself in standard methods. As a test, it is applied to the investigation of the universal spectrum at the van der Waals length scale for two identical Bose atoms in a symmetric harmonic trap, with results compared to the basically exact results obtained from a multiscale quantum-defect theory.

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Imran Khan, Bo Gao. 2007-01-19. Variance minimization variational Monte Carlo method. https://arxiv.org/abs/physics/0701223

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