Programme

O.3 -- Oral, ANSWCCMS-2023

Date: Friday, 10 November 2023

Time: 10:00 - 10:30

Time-dependent spectral functions of the Anderson impurity model in response to a quench: TDNRG study towards observation with time-resolved photoemission spectroscopy

Nghiem Thi Minh Hoa

Phenikaa Institute for Advanced Study, Phenikaa University, 12116 Hanoi, Vietnam

We investigate the formalism within the framework of time-dependent numerical renormalization group (TDNRG) to compute non-equilibrium Green functions, including both the retarded/advanced and lesser/greater Green functions [1]. In the application to the Anderson impurity model following a quench, we analyze the spectral function A(ω,t), obtained from the Fourier transformation of the retarded Green function utilizing Wigner time. The result reveals the evolution of initial and final spectral features at respective negative and positive times. Furthermore, we employ the lesser Green function, specifically, to calculate the time-resolved photoemission current for the Anderson model following a quench, effectively acting as the pump. This investigation allows us to discern the different behaviors that manifest for various resolution times of a Gaussian probe pulse. [1] H. T. M. Nghiem and T. A. Costi, Physical Review B 104, 205113 (2021).

Presenter: Nghiem Thi Minh Hoa