Solver for the electronic V-representation problem of time-dependent density functional theory

Abstract

One route to numerically propagating quantum systems is time-dependent density functional theory (TDDFT). The application of TDDFT to a particular system's time evolution is predicated on V -representability which we have analyzed in a previous publication. Here we describe a newly developed solver for the scalar time-dependent Kohn-Sham potential. We present and interpret the force-balance equation central to our numerical method, describe details of its implementation, and present illustrative numerical results for one-and two-electron systems. A new characterization of V -representability for one-electron systems is also included along with possible improvements and future directions.

Density functionals and Kohn-Sham potentials with minimal wavefunction preparations on a quantum computer

“…Previous attempts to obtain functionals from the quan-tum computer have relied on many measurements of the wavefunction for each system of interest. 13,[49][50][51][52][53] In our view, a worthy goal is to avoid both excessive measurements and re-preparations of the wavefunction especially in the case of time-dependent quantities. 50,54 This work proposes a feasible algorithm that finds the ML model for F [n] on the quantum computer if a groundstate wavefunction is available.…”