Editing Quantum error correction (section)

== Quantum error correction without encoding and parity checks ==
In 2022, research at University of Engineering and Technology Lahore demonstrated error cancellation by inserting single-qubit Z-axis rotation gates into strategically chosen locations of the superconductor quantum circuits.<ref name=":1">{{Cite journal |last1=Ahsan |first1=Muhammad |last2=Naqvi |first2=Syed Abbas Zilqurnain |last3=Anwer |first3=Haider |date=2022-02-18 |title=Quantum circuit engineering for correcting coherent noise |journal=Physical Review A |volume=105 |issue=2 |page=022428 |doi=10.1103/physreva.105.022428 |arxiv=2109.03533 |bibcode=2022PhRvA.105b2428A |s2cid=237442177 |issn=2469-9926}}</ref> The scheme has been shown to effectively correct errors that would otherwise rapidly add up under constructive interference of coherent noise. This is a circuit-level calibration scheme that traces deviations (e.g. sharp dips or notches) in the decoherence curve to detect and localize the coherent error, but does not require encoding or parity measurements.<ref>{{Cite web |last=Steffen |first=Matthias |date=20 Oct 2022 |title=What's the difference between error suppression, error mitigation, and error correction? |url=https://research.ibm.com/blog/quantum-error-suppression-mitigation-correction |access-date=2022-11-26 |website=IBM Research Blog |language=en}}</ref> However, further investigation is needed to establish the effectiveness of this method for the incoherent noise.<ref name=":1" />