Lattice assisted spectroscopy: a generalized scanning tunnelling microscope for ultra-cold atoms

TL;DR

This paper introduces lattice-assisted spectroscopy (LAS), a novel method for measuring local particle and hole spectra in ultracold atom systems using site-resolved imaging, validated through theoretical models and applicable to various quantum phases.

Contribution

The paper presents a new spectroscopy scheme combining perturbation theory and DMRG for local spectral measurements in ultracold lattice systems, extending capabilities of current experimental techniques.

Findings

Validated LAS on 1D superfluid and Mott insulator systems

Demonstrated LAS on edge states of the bosonic SSH model

Extended LAS to access diverse frequency-resolved spectra

Abstract

We show that the possibility to address and image single sites of an optical lattice, now an experimental reality, allows to measure the frequency-resolved local particle and hole spectra of a wide variety of one- and two-dimensional systems of lattice-confined strongly correlated ultracold atoms. Combining perturbation theory and time-dependent DMRG, we validate this scheme of lattice-assisted spectroscopy (LAS) on several example systems, such as the 1D superfluid and Mott insulator, with and without a parabolic trap, and finally on edge states of the bosonic Su-Schrieffer-Heeger model. We also highlight extensions of our basic scheme to obtain an even wider variety of interesting and important frequency resolved spectra.