We introduce a new stochastic method for calculating ground-state properties of quantum systems. Segments of a Langevin random walk guided by a trial wave function are subject to a Metropolis rejection test performed on the time integral of the local energy. The algorithm-which is as simple as variational Monte Carlo-for bosons provides exact expectation values of local observables, as well as their static and dynamic (in imaginary time) response functions, without mixed-estimate nor population-control biases. Our method is demonstrated with a few case applications to (4)He.
Reptation quantum Monte Carlo: A method for unbiased ground-state averages and imaginary-time correlations / Baroni, S.; Moroni, S.. - In: PHYSICAL REVIEW LETTERS. - ISSN 0031-9007. - 82:24(1999), pp. 4745-4748. [10.1103/PhysRevLett.82.4745]
Reptation quantum Monte Carlo: A method for unbiased ground-state averages and imaginary-time correlations
Baroni, S.;Moroni, S.
1999-01-01
Abstract
We introduce a new stochastic method for calculating ground-state properties of quantum systems. Segments of a Langevin random walk guided by a trial wave function are subject to a Metropolis rejection test performed on the time integral of the local energy. The algorithm-which is as simple as variational Monte Carlo-for bosons provides exact expectation values of local observables, as well as their static and dynamic (in imaginary time) response functions, without mixed-estimate nor population-control biases. Our method is demonstrated with a few case applications to (4)He.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
