Physics Colloquium

Quantum Simulation of the Unknown: Observation of Pseudogap Physics in the Fermi–Hubbard Model at Ultralow Temperatures

What happens when quantum simulations become cold enough to surprise us? So far, quantum simulations have primarily served as impressive proof-of-principle demonstrations, realizing a wide range of many-body quantum phases. However, temperatures have remained too high to truly access uncharted regimes relevant to strongly correlated quantum materials.

In this talk, I will present a recent breakthrough in which we use an ultracold-atom realization of the Fermi–Hubbard model to explore pseudogap physics in the doped regime. By achieving a several-fold reduction in temperature, we enter a new regime and observe, unexpectedly, a pronounced peak in the compressibility near 1/8 doping. This feature appears to separate a conventional metallic phase from a pseudogap phase. Furthermore, we measure characteristic signatures of a pseudogap in the excitation spectrum and begin to observe the emergence of spin stripe correlations.

This work represents a key advance in quantum simulation: it demonstrates that we can now address central open questions in condensed matter physics using controlled experiments in regimes that lie at the frontier of classical numerical methods.

Join via Zoom:
https://caltech.zoom.us/j/84497014003
Meeting ID: 844 9701 4003

The colloquium is held in Feynman Lecture Hall, 201 E. Bridge.