# Structure optimization for parameterized quantum circuits

## TL;DR

This paper introduces a method to optimize both the structure and parameters of quantum circuits efficiently, improving performance especially on noisy intermediate-scale quantum computers, demonstrated through simulations and real quantum hardware.

## Contribution

It presents a novel approach for simultaneous structure and parameter optimization in quantum circuits, enhancing performance on NISQ devices.

## Key findings

- Shallow circuits with structure optimization outperform parameter-only updates.
- The method effectively finds ground states in quantum chemistry and physics models.
- Demonstrated success on both simulations and IBM quantum hardware.

## Abstract

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.