Quantum error mitigation and quantum coding

Key Challenge

For leading QEC codes like the surface code, the qubit overhead is often quoted to be around 1000 physical qubits per logical qubits, which means that millions of qubits would be required to perform Shor’s algorithm.

Research Ideas

Almost all leading QEC codes are based on the Calderbank-Shor-Steane (CSS) paradigm, but there are known small non-CSS codes that outperform their CSS counterpart.

QEM has lower hardware requirements and qubit overhead than QEC, but requires more circuit runs.

Methodology

  • We wish to search for larger instances of ‘good’ non-CSS codes for practical implementation.

  • We will use QEM to remove part of the errors so that the cost of QEC is reduced.

  • We will tailor our protocols to different application scenarios where different errors might arise.

The Team

Dan Browne

Lajos Hanzo

Balint Koczor

Zhenyu Cai