Generating multi-atom entanglement by quantum Zeno dynamics in an optical fiber micro cavity (Prof. J. Reichel)

Recent developments in quantum technology show that powerful new forms of quantum dynamics can be obtained when this dichotomy is abandoned and environment coupling is used as part of the state generation. One intriguing example is Quantum Zeno Dynamics (QZD), which combines a unitary evolution U with a simultanous measurement that projects into a multidimensional subspace of the Hilbert space. The measurement effectively restricts the coherent evolution to that subspace. This results in quantum states that would be inaccessible to U alone, and which are potentially interesting for quantum engineering. Here we experimentally demonstrate the use of QZD, based on nondestructive measurement with a high-finesse optical cavity, to deterministically generate different multi-particle entangled states in an ensemble of 36 qubit atoms in less than 5 microseconds.