Preparing random states and benchmarking with many-body quantum chaos

Area of Science:

• Quantum Information Science
• Quantum Dynamics
• Condensed Matter Physics

Background:

• Generating random quantum states is crucial for quantum computing and understanding complex quantum systems.
• Current methods require precise spatio-temporal control, limiting their application.
• Random states are key to understanding quantum circuit complexity, black holes, and quantum advantage.

Purpose of the Study:

• To develop a method for naturally producing random quantum state ensembles.
• To implement an efficient and widely applicable quantum device benchmarking protocol.
• To gain new insights into quantum thermalization and universal correlations.

Main Methods:

• Predicting and observing the emergence of random state ensembles from time-independent Hamiltonian dynamics.
• Utilizing projective measurements and universal correlations between quantum subsystems.
• Developing a fidelity estimation scheme for quantum simulators.

Main Results:

• Demonstrated the natural emergence of random quantum state ensembles.
• Implemented an efficient benchmarking protocol applicable to various quantum systems.
• Achieved accurate fidelity estimation for a 25-atom Rydberg quantum simulator with minimal samples.
• Showcased broad applicability in Hamiltonian parameter estimation and device comparison.

Conclusions:

• The discovery enables efficient generation of random quantum states without complex control.
• Provides new perspectives on quantum thermalization and the role of universal correlations.
• The developed fidelity estimation scheme significantly enhances quantum device characterization and benchmarking.