Reptation Quantum Monte Carlo

S. Baroni; S. Moroni

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arXiv · cond-mat/9808213

Reptation Quantum Monte Carlo

S. Baroni·S. Moroni

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Abstract

We present an elementary and self-contained account of the analogies existing between classical diffusion and the imaginary-time evolution of quantum systems. These analogies are used to develop a new quantum simulation method which allows to calculate the ground-state expectation values of local observables without any mixed estimates nor population-control bias, as well as static and dynamic (in imaginary time) response functions. This method, which we name Reptation Quantum Monte Carlo, is demonstrated with a few case applications to 4He, including the calculation of total and potential energies, static and imaginary-time dependent density response functions, and low-lying excitation energies. Finally, we discuss the relations of our technique with other simulation schemes.

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S. Baroni, S. Moroni. 1998-08-19. Reptation Quantum Monte Carlo. https://arxiv.org/abs/cond-mat/9808213

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