Bounday Condition histograms for modulated phases

TL;DR

This paper introduces a novel method combining fluctuating boundary conditions and histogram techniques to accurately analyze finite size effects in classical and quantum inhomogeneous or incommensurate systems, exemplified on a 2D XY model.

Contribution

It presents a new approach for handling boundary condition effects in numerical simulations of complex systems, applicable to both classical and quantum models.

Findings

Accurately evaluates current-current correlation functions.

Effectively deals with boundary condition influences.

Demonstrates method on a frustrated 2D XY model.

Abstract

Boundary conditions strongly affect the results of numerical computations for finite size inhomogeneous or incommensurate structures. We present a method which allows to deal with this problem, both for ground state and for critical properties: it combines fluctuating boundary conditions and specific histogram techniques. Our approach concerns classical systems possessing a continuous symmetry as well as quantum systems. In particular, current-current correlation functions, which probe large scale coherence of the states, can be accurately evaluated. We illustrate our method on a frustrated two dimensional XY model.