Programme

P.63 -- Poster, VCTP-44

Date: Thursday, 1 August 2019

Time: 08:30 - 10:00

Method of solving the time-dependent Schrödinger equation and its implementation in strong field physics

Cam-Tu Le (1,2), Ngoc-Loan T. Phan (3), Van-Hoang Le (3)

(1) Atomic Molecular and Optical Physics Research Group, Advanced Institute of Materials Science, Ton Duc Thang University, Ho Chi Minh City, Vietnam; (2) Faculty of Applied Sciences, Ton Duc Thang University, Ho Chi Minh City, Vietnam; (3) Department of Physics, Ho Chi Minh City University of Education, Ho Chi Minh City, Vietnam

We establish a method of numerically solving the time-dependent Schrödinger equation (TDSE) for a linear molecule exposed to a linearly polarized laser. For this purpose, we employ the single-active-electron approximation (SAE) for modeling the molecule as a system with one electron moving in the effective potential. This construction is based on the fact that, basically, only electron in the highest accupied molecular orbital (HOMO) interacts with the laser field. In practice, this TDSE+SAE method saves more computational cost than the others, such as the time-dependent Hartree-Fock (TDHF), multiconfiguration time-dependent Hartree-Fock (MCTDHF), and time-dependent density functional theory (TDDFT) methods. The solving process consists of two stages. First, wave functions of the laser-free system are built by solving the time-independent Schrödinger equation to use them as a basis set. Then, solutions of the TDSE are constructed in an expansion of the basis set functions, where the coefficients are time-dependent and can be obtained by the fourth-order Runge-Kutta method. We use the received wave functions further to investigate some nonlinear optic phenomena, such as the high-order harmonic generation (HHG) and the laser-induced electron diffraction (LIED). In this work, we demonstrate HHG spectra from CO molecule responding to a near-infrared laser. The results are compared with other experimental and theoretical data and used in several physics analyses.

Presenter: Le Thi Cam Tu