# Doublon lifetimes in dissipative environments

## TL;DR

This paper investigates how different types of environmental noise affect the lifetime of doublons in a two-electron Hubbard model, revealing that charge noise can stabilize doublons while current noise destabilizes them, with implications for quantum dot systems.

## Contribution

It provides a comparative analysis of charge and current noise effects on doublon decay, combining numerical and analytical methods for the first time.

## Key findings

- Doublon lifetime increases with interaction under charge noise.
- Doublons become less stable with larger interaction under current noise.
- Predicted doublon lifetimes can reach up to 50 ns in quantum dot setups.

## Abstract

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 modelled as a bosonic heat bath that couples to the onsite 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 life time 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 that the doublon life times up to 50 ns.