Dynamical phase error in interacting topological quantum memories

A local Hamiltonian with topological quantum order (TQO) has a robust ground-state degeneracy that makes it an excellent quantum memory candidate. This memory can be corrupted however if part of the state leaves the protected ground-state manifold and returns later with a dynamically accrued phase error. Here we analyze how TQO suppresses this process and use this to quantify the degree to which spectral densities in different topological sectors are correlated. We provide numerical verification of our results by modeling an interacting p-wave superconducting wire.

Automated summary

A local Hamiltonian with topological quantum order can be an excellent candidate for quantum memory due to its robust ground-state degeneracy, but caution is needed to avoid phase errors. The analysis explores how topological quantum order suppresses errors in the system and quantifies the correlation of spectral densities in different topological sectors. This is numerically verified through modeling an interacting p-wave superconducting wire.