Lattice surgery realized on two distance-three repetition codes with superconducting qubits

Area of Science:

• Quantum Computing
• Quantum Error Correction

Background:

• Quantum computers require robust quantum error correction for complex algorithms.
• Current research focuses on low error rates for single logical qubits.
• Entangling logical qubits and performing gate operations are crucial next steps.

Purpose of the Study:

• To demonstrate lattice surgery between two distance-three repetition-code qubits.
• To implement fault-tolerant gate operations on encoded qubits.
• To show functional building blocks for larger-distance codes.

Main Methods:

• Demonstrated lattice surgery by splitting a distance-three surface-code qubit.
• Utilized a quantum circuit fault-tolerant for bit-flip errors.
• Performed operations on two distance-three repetition-code qubits.

Main Results:

• Achieved lattice surgery between encoded qubits.
• Showed improved decoded Z Z logical two-qubit observable compared to non-encoded circuits.
• Validated the technique for superconducting circuits.

Conclusions:

• Lattice surgery is a viable technique for entangling and operating on encoded qubits.
• This work provides essential building blocks for scalable quantum computation.
• Demonstrated progress towards fault-tolerant quantum computing using superconducting circuits.