iSwitch: QEC on Demand via In-Situ Encoding of Bare Qubits for Ion Trap Architectures

Understand

Recent advances in quantum hardware and error correction have paved the way for early fault-tolerant (EFT) quantum computing.

• We propose iSwitch, a hybrid system architecture for trapped-ion quantum computers (TIQC) that exploits ultra-high-fidelity single-qubit gates and efficient logical CNOTs enabled by ion shuttling.
• iSwitch employs bare qubits for single-qubit operations and QEC-encoded logical qubits for two-qubit gates, avoiding full logical encoding, gate synthesis, and magic state distillation.
• To enable this selective encoding, we develop a low-noise conversion protocol between bare and logical qubits, a hybrid instruction set tailored to 2D TIQC layouts, and a compiler that minimizes conversion overhead and optimizes scheduling.