Local control and mixed dimensions: Exploring high-temperature superconductivity in optical lattices

TL;DR

This paper proposes a versatile quantum simulation toolbox using optical lattices with local control and bilayer capabilities to explore high-temperature superconductivity, including mixed-dimensional models and d-wave pairing.

Contribution

It introduces new schemes for simulating mixed-dimensional bilayer models and observing d-wave pairing in optical lattices, advancing the study of high-temperature superconductors.

Findings

Realization of a mixed-dimensional bilayer model for nickelates.

Observation of d-wave pairing order in a 2D Fermi-Hubbard model.

Scheme for measuring momentum-resolved dopant densities.

Abstract

The simulation of high-temperature superconducting materials by implementing strongly correlated fermionic models in optical lattices is one of the major objectives in the field of analog quantum simulation. Here we show that local control and optical bilayer capabilities combined with spatially resolved measurements create a versatile toolbox to study fundamental properties of both nickelate and cuprate high-temperature superconductors. On the one hand, we present a scheme to implement a mixed-dimensional (mixD) bilayer model that has been proposed to capture the essential pairing physics of pressurized bilayer nickelates. This allows for the long-sought realization of a state with long-range superconducting order in current lattice quantum simulation machines. In particular, we show how coherent pairing correlations can be accessed in a partially particle-hole transformed and rotated basis. On the other hand, we demonstrate that control of local gates enables the observation of $d$-wave pairing order in the two-dimensional (single-layer) repulsive Fermi-Hubbard model through the simulation of a system with attractive interactions. Lastly, we introduce a scheme to measure momentum-resolved dopant densities, providing access to observables complementary to solid-state experiments -- which is of particular interest for future studies of the enigmatic pseudogap phase appearing in cuprates.