High-Fidelity Magic-State Preparation with a Biased-Noise Architecture

Abstract

Magic state distillation is a resource intensive subroutine that consumes noisy input states to produce high-fidelity resource states that are used to perform logical operations in practical quantum-computing architectures. The resource cost of magic state distillation can be reduced by improving the fidelity of the raw input states. To this end, we propose an initialization protocol that offers a quadratic improvement in the error rate of the input magic states in architectures with biased noise. This is achieved by preparing an error-detecting code which detects the dominant errors that occur during state preparation. We obtain this advantage by exploiting the native gate operations of an underlying qubit architecture that experiences biases in its noise profile. We perform simulations to analyze the performance of our protocol with the XZZX surface code. Even at modest physical parameters with a two-qubit gate error rate of $0.7\%$ and total probability of dominant errors in the gate $O(10^3)$ larger compared to that of non-dominant errors, we find that our preparation scheme delivers magic states with logical error rate $O(10^{-8})$ after a single round of the standard 15-to-1 distillation protocol; two orders of magnitude lower than using conventional state preparation. Our approach therefore promises considerable savings in overheads with near-term technology.

References in corpus (11)

• Surface codes: Towards practical large-scale quantum computation
• Confining the state of light to a quantum manifold by engineered two-photon loss
• Magic state distillation with low overhead
• Fault-tolerant quantum computation against biased noise
• Focus beyond quadratic speedups for error-corrected quantum advantage
• Improved magic states distillation for quantum universality
• Multilevel distillation of magic states for quantum computing
• A magic state's fidelity can be superior to the operations that created it
• Reducing the quantum computing overhead with complex gate distillation
• Quantum computing by color-code lattice surgery
• Engineering fast bias-preserving gates on stabilized cat qubits

Cited by in corpus (10)

• Encoding a magic state with beyond break-even fidelity
• Partially Fault-tolerant Quantum Computing Architecture with Error-corrected Clifford Gates and Space-time Efficient Analog Rotations
• Hybrid Oscillator-Qubit Quantum Processors: Instruction Set Architectures, Abstract Machine Models, and Applications
• Fault-tolerant Post-Selection for Low Overhead Magic State Preparation
• Mitigating errors in logical qubits
• Hybrid cat-transmon architecture for scalable, hardware-efficient quantum error correction
• Surface Code with Imperfect Erasure Checks
• Magic State Injection with Erasure Qubits
• Unfolded distillation: very low-cost magic state preparation for biased-noise qubits
• Logical Noise Bias in Magic State Injection