The hybrid surface flux method for the ionization amplitude extraction from the calculated wavefunction

TL;DR

The paper introduces a hybrid surface flux method that efficiently extracts ionization amplitudes from the TDSE by combining two existing methods, reducing computational domain and time requirements.

Contribution

A novel hybrid method that merges t-SURFF and wavepacket source approaches for improved ionization amplitude extraction from TDSE solutions.

Findings

Method effectively combines advantages of parent methods.

Allows extraction within small spatial and temporal domains.

Uses exterior complex scaling for boundary conditions.

Abstract

A method is proposed for extracting ionization amplitudes from the solution of the time-dependent Schr\"odinger equation (TDSE) describing a system in a time-dependent external field. The method is a hybrid of two earlier developed methods, the time-dependent surface flux (t-SURFF) method and the method using the propagated wavepacket as the source term in a time-independent driven Schr\"odinger equation with the field-free Hamiltonian. It is demonstrated that the method combines the advantages of the parent ones and allows the extraction of ionization amplitudes by solving the TDSE within a small spatial domain (with the boundary conditions provided by exterior complex scaling) and a time interval, not exceeding the external field pulse duration.