NOTICE: Due to a lapse in annual appropriations, most of this website is not being updated. Learn more.
Form submissions will still be accepted but will not receive responses at this time. Sections of this site for programs using non-appropriated funds (such as NVLAP) or those that are excepted from the shutdown (such as CHIPS and NVD) will continue to be updated.
An official website of the United States government
Here’s how you know
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
Symmetry breaking and error correction in open quantum systems
Published
Author(s)
Simon K. Lieu, Ron Belyansky, Jeremy T. Young, Rex Lundgren, Victor Albert, Alexey Gorshkov
Abstract
Symmetry-breaking transitions are a well-understood phenomenon of closed quantum systems in quantum optics, condensed matter, and high energy physics. However, symmetry breaking in open systems is less thoroughly understood, in part due to the richer steady-state and symmetry structure that such systems possess. For the prototypical open system---a Lindbladian---a unitary symmetry can be imposed in a ''weak'' or a ''strong'' way. We characterize the possible $\mathbbZ}_n$ symmetry breaking transitions for both cases. In the case of $\mathbbZ}_2$, a weak-symmetry-broken phase guarantees at most a classical bit steady-state structure, while a strong-symmetry-broken phase admits a partially-protected steady-state qubit. Viewing photonic cat qubits through the lens of strong-symmetry breaking, we show how to dynamically recover the logical information after any gap-preserving strong-symmetric error; such recovery becomes perfect exponentially quickly in the number of photons. Our study forges a connection between driven-dissipative phase transitions and error correction.
Lieu, S.
, Belyansky, R.
, Young, J.
, Lundgren, R.
, Albert, V.
and Gorshkov, A.
(2020),
Symmetry breaking and error correction in open quantum systems, Physical Review Letters, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=930889
(Accessed October 14, 2025)