Adaptive Variational Quantum Simulations of Periodic Materials Using Qubit-Encoded Wave Functions

Area of Science:

• Quantum computing
• Materials science
• Computational chemistry

Background:

• Near-term quantum devices are limited by noise, restricting simulations to shallow circuits.
• Accurate quantum simulations are crucial for advancing materials design and discovery.

Purpose of the Study:

• To develop circuit-efficient variational quantum eigensolver (VQE) simulations for periodic materials.
• To reduce the circuit depth required for accurate quantum simulations of materials.

Main Methods:

• Utilized qubit-encoded wave functions with Adaptive Derivative-Assembled Pseudo-Trotter (ADAPT) VQE.
• Introduced operator pools with anti-Hermitian one- and two-body qubit excitation/flipping operators.
• Integrated variance extrapolation with ADAPT-VQE for enhanced accuracy.

Main Results:

• Demonstrated accurate prediction of ground-state energy for periodic systems.
• Significantly reduced circuit depth compared to Fermion-encoded algorithms.
• Achieved scalable and precise simulations through enhanced accuracy and reduced depth.

Conclusions:

• ADAPT-VQE with qubit encoding offers a powerful approach for simulating periodic materials.
• The developed methods enable more feasible and accurate quantum simulations on near-term devices.
• This work paves the way for utilizing quantum computing in practical materials design.