Fault-tolerant quantum computation without distillation on a 2D device

Area of Science:

• Quantum computing
• Fault-tolerant quantum computation
• Surface codes

Background:

• Looped pipeline architectures offer bounded non-local connectivity for physical qubits.
• Implementing non-Clifford gates is crucial for universal quantum computation.

Purpose of the Study:

• To evaluate the efficiency of looped pipeline architectures for implementing fault-tolerant non-Clifford gates in 2D surface codes.
• To compare the resource cost of this method with magic state distillation.

Main Methods:

• Utilizing looped pipeline architectures with short-range qubit shuttling.
• Implementing fault-tolerant non-Clifford gates within 2D surface codes.
• Analyzing the complexity of the required shuttling schedule.
• Comparing resource costs against magic state distillation.

Main Results:

• Looped pipeline architectures can efficiently implement fault-tolerant non-Clifford gates.
• The required shuttling schedule is only marginally more complex than for standard 2D surface codes.
• Magic state distillation is currently more resource-efficient.
• High costs for non-Clifford gates are linked to the performance of just-in-time decoders.

Conclusions:

• The efficiency of non-Clifford gate implementation in looped pipeline architectures is hindered by decoder performance.
• Optimizing just-in-time decoders presents a significant opportunity for improving resource efficiency.
• Further research into decoder optimization is warranted for advancing fault-tolerant quantum computing.