Computing molecular excited states on a D-Wave quantum annealer.

Area of Science:

• Quantum computing
• Computational chemistry
• Molecular modeling

Background:

• Quantum computing offers new possibilities for electronic structure calculations.
• Quantum annealers, a type of adiabatic quantum computer, have potential yet to be fully explored.
• Simulating excited electronic states is crucial for fields like photovoltaics and nanoscience.

Purpose of the Study:

• To demonstrate the use of a D-Wave quantum annealer for calculating excited electronic states of molecular systems.
• To apply quantum annealing to solve eigenvalue equations derived from TDHF and TDDFT within the TDA.
• To assess the capability of quantum annealers for molecular excited state simulations.

Main Methods:

• Utilized a D-Wave quantum annealer to solve Tamm-Dancoff approximation (TDA) eigenvalue equations.
• Employed time-dependent Hartree-Fock (TDHF) and time-dependent density-functional theory (TDDFT) methods.
• Used the previously developed Quantum Annealer Eigensolver (QAE) for calculations.

Main Results:

• Successfully reproduced basis set convergence for the [Formula: see text] molecule.
• Calculated transition dipole moments and oscillator strengths for molecular systems.
• Computed excited state potential energy profiles for [Formula: see text] as a function of geometry.

Conclusions:

• Quantum annealers are viable tools for calculating molecular excited electronic states.
• The accuracy of quantum annealing results depends on the underlying meta-heuristic software (qbsolv).
• This quantum approach advances computational chemistry for materials science applications.