Guy
Cohen
Tel Aviv University
Simulating the time evolution of many-body quantum systems remains a major challenge in modern theory. In this talk, I will present my work on controlled diagrammatic Monte Carlo approaches to the dynamics of correlated quantum impurity models [1–3], systems where a small interacting region is coupled to large noninteracting baths. While impurity models play a central role in a variety of contexts ranging from nonequilibrium transport to materials science, I will focus on the paradigmatic physics of the sub-Ohmic spin–boson model. There, we recently showed how transient dynamics after a quench reveals signatures of dissipation-driven quantum criticality and a dynamical phase structure that differs from equilibrium expectations [4]. Finally, I will discuss how this work fits into a broader research vision centered on predictive simulation of quantum many-body systems in and out of equilibrium.
[1] G. Cohen, E. Gull, D. R. Reichman, and A. J. Millis, Phys. Rev. Lett. 115, 266802 (2015).
[2] E. Eidelstein, E. Gull, and G. Cohen, Phys. Rev. Lett. 124, 206405 (2020).
[3] A. Erpenbeck, E. Gull, and G. Cohen, Phys. Rev. Lett. 130, 186301 (2023).
[4] O. Goulko, H.-T. Chen, M. Goldstein, and G. Cohen, Phys. Rev. Lett. 134, 056502 (2025).
https://us06web.zoom.us/j/87086754153?pwd=5j9rvjOMWbi0rEdU2IUXAi8WFkjHqo.1
