2016/01/30 by P. C. Stancil, H. You, Stancil, P. C. +11 · 1 citation
Computer Science · Physics and Astronomy · #Chemical Physics (physics.chem-ph) #FOS: Physical sciences #Quantum Computing Algorithms and Architecture #Quantum Information and Cryptography #Quantum Mechanics and Applications #Quantum Physics (quant-ph) #physics.chem-ph #quant-ph
paper · pdf · doi:10.48550/arxiv.1602.00063
arxiv created 2016/01/30 · openalex publication_date 2016/01/30 · arxiv updated 2016/02/02 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The single excitation subspace (SES) method for universal quantum simulation is investigated for a number of diatomic molecular collision complexes. Assuming a system of n tunably-coupled, and fully-connected superconducting qubits, computations are performed in the n-dimensional SES which maps directly to an n-channel collision problem within a diabatic molecular wave function representation. Here we outline the approach on a classical computer to solve the time-dependent Schrödinger equation in an n-dimensional molecular basis - the so-called semiclassical molecular-orbital close-coupling (SCMOCC) method - and extend the treatment beyond the straight-line, constant-velocity approximation which is restricted to large kinetic energies (\gtrsim 0.1 keV/u). We explore various multichannel potential averaging schemes and an Ehrenfest symmetrization approach to allow for the application of the SCMOCC method to much lower collision energies (approaching 1 eV/u). In addition, a computational efficiency study for various propagators is performed to speed-up the calculations on classical computers. These computations are repeated for the simulation of the SES approach assuming typical parameters for realistic pretheshold superconducting quantum computing hardware. The feasibility of applying future SES processors to the quantum dynamics of large molecular collision systems is briefly discussed.