Volume extrapolation via eigenvector continuation

TL;DR

This paper introduces finite-volume eigenvector continuation (FVEC), a method to accurately extrapolate quantum system simulations across various box sizes by matching periodic functions, with practical implementation using plane-wave states.

Contribution

The paper extends eigenvector continuation to finite-volume systems, providing a formal justification and practical implementation for large-range box size extrapolations in quantum simulations.

Findings

FVEC accurately extrapolates quantum simulations across box sizes.

Implementation using plane-wave states is effective.

The method is validated through several applications.

Abstract

We develop an extension of eigenvector continuation (EC) that makes it possible to extrapolate simulations of quantum systems in finite periodic boxes across large ranges of box sizes. The formal justification for this approach, which we call finite-volume eigenvector continuation (FVEC), is provided by matching periodic functions at different box sizes. As concrete FVEC implementation we use a discrete variable representation based on plane-wave states and present several applications calculated within this framework.