English

Candidate for a passively protected quantum memory in two dimensions

Quantum Physics 2023-03-03 v3 Mesoscale and Nanoscale Physics Strongly Correlated Electrons Superconductivity

Abstract

An interesting problem in the field of quantum error correction involves finding a physical system that hosts a ``passively protected quantum memory,'' defined as an encoded qubit coupled to an environment that naturally wants to correct errors. To date, a quantum memory stable against finite-temperature effects is only known in four spatial dimensions or higher. Here, we take a different approach to realize a stable quantum memory by relying on a driven-dissipative environment. We propose a new model, the photonic-Ising model, which appears to passively correct against both bit-flip and phase-flip errors in two dimensions: A square lattice composed of photonic ``cat qubits'' coupled via dissipative terms which tend to fix errors locally. Inspired by the presence of two distinct Z2\mathbb{Z}_2-symmetry-broken phases, our scheme relies on Ising-like dissipators to protect against bit flips and on a driven-dissipative photonic environment to protect against phase flips. We also discuss possible ways to realize the photonic-Ising model.

Keywords

Cite

@article{arxiv.2205.09767,
  title  = {Candidate for a passively protected quantum memory in two dimensions},
  author = {Simon Lieu and Yu-Jie Liu and Alexey V. Gorshkov},
  journal= {arXiv preprint arXiv:2205.09767},
  year   = {2023}
}
R2 v1 2026-06-24T11:22:43.299Z