Optimal robust control of cat-state qubits against parameter imperfections

Area of Science:

• Quantum Computing
• Quantum Information Science

Background:

• Cat-state qubits, derived from photonic coherent states, are vital for fault-tolerant quantum computing.
• These qubits are susceptible to biased noise, with bit-flip errors being the most significant.

Purpose of the Study:

• To propose an optimally robust protocol for high-fidelity state transfer in cat-state qubits.
• To address and mitigate the dominant bit-flip errors in these quantum systems.

Main Methods:

• Utilized shortcuts to adiabaticity (STA) as a control method.
• Constructed an STA protocol based on the Lewis-Riesenfeld invariant.
• Analyzed the stability of the protocol against various perturbations for bit-flipping.

Main Results:

• Demonstrated robust bit-flipping against systematic errors through numerical simulations.
• Achieved a final population of the target state ≥99% even with a 20% parameter imperfection rate.
• The protocol ensures fast and robust bit-flipping operations.

Conclusions:

• The optimally robust control protocol offers a feasible approach for fault-tolerant quantum computation.
• This method enhances the scalability of quantum computing systems.
• Successfully mitigated dominant bit-flip errors in cat-state qubits.