Researchers from the Quantum AI Team at Google are working on quantum error correction for quantum devices. They identify and address key errors that affect the performance of qubits, which are the building blocks of quantum computers.
Understanding Leakage in Qubits
Qubits are used to carry out computations in quantum computers. Unlike ideal qubits, which have only two computational levels, transmon qubits have many additional states with higher energies than the computational excited state. These extra states can interfere with the normal operation of the qubit, causing what is known as leakage.
Impact of Leakage on Quantum Error Correction
Leakage is a significant challenge for quantum error correction (QEC) strategies. Errors caused by leakage can accumulate and spread between different qubits in the quantum device, making it challenging to diagnose and correct the errors using QEC algorithms.
Developing Solutions for Leakage
Researchers have developed a new quantum operation called data qubit leakage removal (DQLR), which specifically targets and converts leakage states into computational states in the data qubit and a neighboring measure qubit. This new approach is showing promising results in removing and minimizing the impact of leakage on quantum devices.
Conclusion
Quantum error correction is crucial for the successful development of practical quantum computers. By understanding and addressing the challenges of leakage in qubits, researchers are making significant progress in improving the stability and performance of quantum devices.
By Kevin Miao and Matt McEwen, Research Scientists, Quantum AI Team