Exhaustive search for optimal molecular geometries using imaginary-time evolution on a quantum computer

Understand

We propose a nonvariational scheme for geometry optimization of molecules for the first-quantized eigensolver, a recently proposed framework for quantum chemistry using the probabilistic imaginary-time evolution (PITE) on a quantum computer.

• While the electrons in a molecule are treated in the scheme as quantum mechanical particles, the nuclei are treated as classical point charges.
• We encode both electronic states and candidate molecular geometries as a superposition of many-qubit states, leading to quantum advantage.
• The histogram formed by outcomes of repeated measurements gives the global minimum of the energy surface.