1202.5191 (Jonas A. Mlynek et al.)

Time Resolved Collective Entanglement Dynamics in Cavity Quantum
Electrodynamics    [PDF]

Jonas A. Mlynek, Abdufarrukh A. Abdumalikov Jr., Johannes M. Fink, Lars Steffen, Matthias Baur, Christian Lang, Arjan F. van Loo, Andreas Wallraff

Nonlinearity and entanglement are two important indications by which physical
systems can be identified as non-classical. We study the dynamics of the
resonant interaction of up to N=3 two-level systems and a single mode of the
electromagnetic field. We focus on a single excitation dynamically shared in
this fourpartite system. We observe coherent vacuum Rabi oscillations and their
nonlinear square root N speed-up in frequency by tracking the populations of
all three qubits and the resonator. We use full quantum state tomography to
verify that the dynamics generates a maximally entangled 3-qubit W-state when
the cavity returns to the vacuum state.

View original: http://arxiv.org/abs/1202.5191