Enhanced nematicity in the psuedogap regime of the Hubbard model

Studying the low temperature phases of the Hubbard model is central to understanding the physics of cuprate superconductors and other quantum materials. Much debate centers on how the anomalous 'pseudogapped' metallic state at intermediate temperatures relates to ground-state symmetry-breaking states such as stripes or superconductivity. Experiments on cuprates have provided evidence for electronic nematic order in the pseudogap regime, i.e. broken rotational symmetry without loss of translational symmetry, as a precursor to stripe formation. Here we report on the observation of an enhanced nematic susceptibility to a tunneling imbalance in the Hubbard model at low temperatures and intermediate doping using a cold-atom quantum simulator. We study the evolution of the nematic response versus interaction strength and temperature, and find the maximum occurs in close proximity to a previously observed compressibility maximum. We further explore the link between nematicity and charge order by introducing a controlled disorder potential to suppress the charge correlation length. We find that while spin correlations are enhanced in the presence of disorder, the nematic susceptibility is reduced. Our results experimentally demonstrate enhanced nematicity in the pseudogap regime of the Hubbard model, and provide evidence linking nematicity and charge order. Furthermore, this work demonstrates the utility of quantum simulation in addressing frontier problems in correlated electron physics.