UChicago PME QSE Seminar: Sarang Gopalakrishnan

Surprises in the weak-noise limit

The coherent quantum dynamics of large systems is exponentially hard to simulate on a classical computer. Many physically relevant quantities (such as diffusion constants in generic systems) behave smoothly in the zero-noise limit, so the noiseless value can be efficiently computed by extrapolation: a strongly interacting many-body system “acts as its own bath,” so it is relatively insensitive to coupling to an outside environment. Gopalakrishnan will introduce a family of simple correlation functions whose asymptotic behavior senses quantum coherence at arbitrary temperatures: they decay exponentially in the presence of noise and subexponentially in isolated systems, due to a mechanism we call diffusion-limited dephasing.

Faculty host: Aashish Clerk

Zoom link: https://uchicagogroup.zoom.us/j/98692118711?pwd=OuP2Fl7cbWHpyaEcx1meqz9HggTf6U.1