Quantum Phase Transitions with Photons and Polaritons
Michael J. Hartmann, Fernando G. S. L. Brandão, Martin Bodo Plenio
The experimental observation of quantum phenomena in strongly correlated many particle systems is difficult because of the short length- and timescales involved. Obtaining at the same time detailed control of individual constituents appears even more challenging and thus to date inhibits employing such systems as quantum information processing devices. Substantial progress to overcome these problems has been achieved with cold atoms in optical lattices, where a detailed control of collective properties is feasible. However it is very difficult to address and hence control or measure individual sites [1, 2]. In this work, we demonstrate that polaritons, combined atom and photon excitations, in an array of cavities can form a strongly interacting many body system [3]. This scheme has several advantages: First of all, individual particles can, by construction, be controlled and measured. In contrast to optical lattices, it therefore allows to create inhomogeneous systems where different phases may coexists in adjacent spatial regions. Finally not only an effective Bose- Hubbard Hamiltonian might be created but several different many body systems including spin chains.
International Conference on Quantum Information•Jan 1, 2007•1 citation