Abstract

We give a prescription for finding optimized correlation functions for the extraction of the gap to the first excited state within quantum Monte Carlo simulations. We demonstrate that optimized correlation functions provide a more accurate reading of the gap when compared to other “nonoptimized” correlation functions and are generally characterized by considerably larger signal-to-noise ratios. We also analyze the cost of the procedure and show that it is not computationally demanding. We illustrate the effectiveness of the proposed procedure by analyzing several exemplary many-body systems of interacting spin- particles.

Date

January 1, 1970

Authors

Itay Hen

Journal

Physical Review E—Statistical, Nonlinear, and Soft Matter Physics

Volume

85

Issue

3

Pages

036705

Publisher

American Physical Society