Quantum information processing and quantum metrology with atomic ensembles Eugene Polzik, Niels Bohr Institute, Copenhagen

In recent years engineering of quantum states of macroscopic atomic ensembles allowed us to reach the level of precision below the quantum fluctuations dictated by the Heisenberg uncertainty principle for independent atoms. In the talk I will discuss how such precision quantum engineering can be achieved via a quantum interface of atomic ensembles with light. Key operations, such as generation of entangled states of atoms and light, quantum non-demolition measurements, and swapping of quantum states between photons and atoms will be reviewed. Applications range from quantum teleportation of light onto atoms, to quantum memory for light, to magnetometry with record sensitivity, and to atom clocks.