Candidate for a self-correcting quantum memory in two dimensions

Speaker: Simon Lieu, UMD

Date: Jun 7, 2022 11:00 am

Location: ATL 3100A
https://umd.zoom.us/j/2821742741?pwd=SWJSRm1DTGFoYUtVMllVSEo5bzdmdz09

Abstract:

An interesting problem in the field of quantum error correction involves finding a physical system that hosts a “self-correcting 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 which appears to self-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 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.