Structure optimization for parameterized quantum circuits

We propose an efficient method for simultaneously optimizing both the structure and parameter values of quantum circuits with only a small computational overhead. Shallow circuits that use structure optimization perform significantly better than circuits that use parameter updates alone, making this method particularly suitable for noisy intermediate-scale quantum computers. We demonstrate the method for optimizing a variational quantum eigensolver for finding the ground states of Lithium Hydride and the Heisenberg model in simulation, and for finding the ground state of Hydrogen gas on the IBM Melbourne quantum computer.

Automated summary

Our proposed method efficiently optimizes both the structure and parameter values of quantum circuits with minimal computational overhead, showing better performance for shallow circuits with structure optimization, making it suitable for noisy intermediate-scale quantum computers. Demonstrated by optimizing a variational quantum eigensolver for finding ground states of Lithium Hydride and the Heisenberg model in simulation, and for finding the ground state of Hydrogen gas on the IBM Melbourne quantum computer.