Miguel Bello, Sigmund Kohler, and Gloria Platero
Phys. Rev. B 96,045408 (2017)
We study the dissipative decay of states with a doubly occupied site in a two-electron Hubbard model, known as doublons. For the environment, we consider charge and current noise, which are modeled as a bosonic heat bath that couples to the on-site energies and the tunnel couplings, respectively. It turns out that the dissipative decay depends qualitatively on the type of environment, as for charge noise, the lifetime grows with the electron-electron interaction. For current noise, by contrast, doublons become increasingly unstable with larger interaction. Numerical studies within a Bloch-Redfield approach are complemented by analytical estimates for the decay rates. For typical quantum dot parameters, we predict doublon lifetimes up to 50 ns.