Interaction Spectroscopy of a Two-component Mott Insulator

TL;DR

This study precisely measures interaction strengths in a two-component Mott insulator of bosonic atoms, enabling better understanding and control of quantum phases and magnetic spin models.

Contribution

It introduces an empirical method using RF transitions and interaction blockade to accurately determine hyperfine state interactions in a lattice.

Findings

Mapped interactions of $^7$Li hyperfine states across magnetic fields

Identified Feshbach resonances with high sensitivity

Highlighted regions suitable for magnetic spin model realization

Abstract

We prepare and study a two-component Mott insulator of bosonic atoms with two particles per site. The mapping of this system to a magnetic spin model, and the subsequent study of its quantum phases, require a detailed knowledge of the interaction strengths of the two components. In this work, we use radio frequency (RF) transitions and an on-site interaction blockade for precise, empirical determination of the interaction strengths of different combinations of hyperfine states on a single lattice site. We create a map of the interactions of the lowest two hyperfine states of $^7$Li as a function of magnetic field, including measurements of several Feshbach resonances with unprecedented sensitivity, and we identify promising regions for the realization of magnetic spin models.