Hopping modulation in a one-dimensional Fermi-Hubbard Hamiltonian

TL;DR

This paper investigates how periodic modulation of hopping affects a strongly interacting 1D Fermi gas, revealing spectral features through double occupancy measurements and connecting these to Bethe ansatz solutions.

Contribution

It provides an essentially exact analysis of the system’s response to hopping modulation, linking spectral features to observable double occupancy dynamics in a 1D Fermi-Hubbard model.

Findings

Double occupancy shows a non-trivial frequency dependence.

Spectral features are related to Bethe ansatz solutions.

Discrete spectrum is reflected in long-time double occupancy.

Abstract

We consider a strongly repulsive two-component Fermi gas in a one-dimensional (1D) optical lattice described in terms of a Hubbard Hamiltonian. We analyze the response of the system to a periodic modulation of the hopping amplitude in presence of large two body interaction. By (essentially) exact simulations of the time evolution, we find a non-trivial double occupancy frequency dependence. We show how the dependence relates to the spectral features of the system given by the Bethe ansatz. The discrete nature of the spectrum is clearly reflected in the double occupancy after long enough modulation time. We also discuss the implications of the 1D results to experiments in higher dimensional systems.