Grid-based methods for chemistry simulations on a quantum computer.

Area of Science:

• Quantum Computing
• Computational Chemistry
• Quantum Simulation

Background:

• First-quantized, grid-based methods are well-suited for quantum computers.
• Current quantum hardware limitations (qubit count and quality) hinder exploration of these methods.
• Emulated quantum computers offer a viable platform for near-term research.

Purpose of the Study:

• To evaluate the performance of first-quantized, grid-based algorithms on emulated quantum computers.
• To model 2D and 3D atoms with single and paired particles using resource-frugal quantum algorithms.
• To assess various Hamiltonian simulation techniques within the split-operator QFT (SO-QFT) paradigm.

Main Methods:

• Utilized exactly emulated quantum computers with up to 36 qubits.
• Executed deep yet resource-frugal algorithms for quantum chemistry modeling.
• Applied the split-operator QFT (SO-QFT) Hamiltonian simulation paradigm.

Main Results:

• Successfully modeled 2D and 3D atoms, including ground state preparation, energy estimation, scattering, and ionization dynamics.
• Evaluated established and novel protocols within the SO-QFT framework.
• Demonstrated strong performance of the grid-based method, despite identified restrictions.

Conclusions:

• First-quantized, grid-based methods are effective for quantum chemistry simulations on emulated quantum computers.
• These methods are expected to be dominant in the early fault-tolerant quantum computing era.
• The study validates the potential of quantum computing for advancing computational chemistry.