CASUS Institute Seminar, Joonho Lee, Columbia University

The development of quantum chemistry tools has been focused mainly on the electronic ground state within the Born-Oppenheimer approximation. Over the past few years, several research groups have extended the ground state electronic quantum chemistry methods to finite temperature as well as coupled electron-phonon systems. In this talk, we will discuss how these generalizations are achieved within the framework of auxiliary-field quantum Monte Carlo (AFQMC). We will discuss the performance of AFQMC for the uniform electron gas in the warm-dense regime as well as for the Hubbard-Holstein model with various electron-phonon coupling strengths. Lastly, if there is enough time, we will discuss a general strategy for AFQMC to compute spectral functions to access excited state information without analytic continuation.