Multi-qubit entanglement and algorithms on a neutral-atom quantum computer

Area of Science:

• Quantum Computing
• Atomic Physics

Background:

• Gate-model quantum computers require scalability and high-fidelity operations.
• Neutral-atom hyperfine qubits offer inherent scalability and long coherence times.
• Rydberg states provide strong entangling interactions crucial for quantum computation.

Purpose of the Study:

• To demonstrate quantum algorithms on a programmable neutral-atom quantum computer.
• To showcase the potential of neutral-atom arrays for universal quantum computation.
• To explore the preparation of non-classical states for quantum-enhanced sensing.

Main Methods:

• Utilized a gate-model neutral-atom quantum computer with individually addressed qubits.
• Employed an architecture with tightly focused optical beams scanned across a 2D qubit array.
• Implemented algorithms including GHZ state preparation, quantum phase estimation, and QAOA.

Main Results:

• Successfully prepared entangled Greenberger-Horne-Zeilinger (GHZ) states with up to six qubits.
• Demonstrated quantum phase estimation for a chemistry problem.
• Executed the Quantum Approximate Optimization Algorithm (QAOA) for the MaxCut problem.

Conclusions:

• Neutral-atom qubit arrays exhibit emergent capabilities for universal, programmable quantum computation.
• The demonstrated algorithms highlight the system's potential for complex problem-solving.
• The technology is suitable for preparing non-classical states for quantum-enhanced sensing applications.