Quantum Error Correction with the GKP Code and Concatenation with Stabilizer Codes
Quantum Computing (Stanford Encyclopedia of Philosophy)
I hereby declare that I am the sole author of this thesis. This is a true copy of the thesis, including any required final revisions, as accepted by my examiners. Quantum error correction is the backbone of fault-tolerant quantum computation, a necessary requirement for any large scale quantum computer.
Skepticism was raised along with the rapid development because quantum systems are fragile to environmental noise and it is a critical issue how to overcome unavoidable interactions with environment. We consider quantum error correction, a standard tool to combat noise in quantum information science, in the context of quantum sensing. To be specific, we study the behavior of quantum sensors under environmental noise and identify the sensing limits of noisy quantum sensors. Surprisingly, the sensing limits are achievable using novel quantum error correction protocols which balance the trade-off between the sensitivity enhancement and the noise reduction.