Coherent collisional decoherence

Understand

We study the decoherence of a system of $N$ non-interacting heavy particles (atoms) due to coherent scattering with a background gas.

• We introduce a framework for computing the induced phase shift and loss of contrast for arbitrary preparations of $N$-particle quantum states.
• We find phase shifts that are inherently $(N\geq 2)$-body effects and may be searched for in future experiments.
• We analyze simple setups, including a two-mode approximation of an interferometer.