Quantum matter coupled to enhanced optical fields in confined geometries such as resonators and waveguides offer a promising platform to study emergent phenomena far-from-equilibrium . In my talk I will discuss our recent efforts [2,3,4] at understanding what a quantum phase transition of photons may look like in a lattice of Cavity Quantum Electrodynamics systems, where photons become itinerant. Surprisingly this has lead us back to the very origin of Quantum Electrodynamics and the Quantum Theory, namely to Planck and Einstein’s theory of thermal cavity radiation. We find a modification to the Planck-Einstein theory due to the backaction from (material) oscillators and show that a Cavity QED network displays an instability towards a ferroelectric phase when light-matter coupling is sufficiently increased. The true potential of coupled light-matter systems is however unleashed in driven Cavity QED networks. I will discuss a general method to use photon-mediated interactions between qubits to drive them to a long-distance entangled state with an arbitrarily long lifetime . We find that photon-mediated interactions provide a highly versatile toolbox to engineer the unitary and dissipative dynamics of spatially separated qubits, with important implications for dissipative stabilization of pure many-body states of qubits . The N=2 version of this protocol  has recently been demonstrated  in a 3D superconducting circuit architecture to dissipatively stabilize a target Bell state of two transmon qubits residing in separate cavities.
 A. Houck, H. E. Tureci, J. Koch, Nature Physics 8, 292 (2012).
 M. Schiro, M. Bordyuh, B. Oztop, H. E. Tureci, Phys. Rev. Lett. 109, 053601 (2012).
 M. Schiro, M. Bordyuh, B. Oztop, H. E. Tureci, J. Phys. B 46, 224021 (2013).
 M. Schiro et al, arxiv:1503.04456
 C. Aron, M. Kulkarni, H. E. Tureci, Phys. Rev. A 90, 062305 (2014).
 C. Aron, M. Kulkarni, H. E. Tureci, arxiv:1412.8477
 M. E. Schwartz et al., arXiv:1511.00702
Bio: Hakan E Tureci is an Assistant Professor in the Department of Electrical Engineering at Princeton University. Prior to joining Princeton faculty, he obtained a BS degree in Physics from Bilkent University and received his Ph.D. from Yale University in 2003. He did his postdoctoral work at Yale University and at the Institute for Quantum Electronics at ETH Zurich. In 2009, he was appointed SNF Professor for Mesoscopic Quantum Optics at ETH. He moved to Princeton University in 2010. His research focuses on theoretical problems in quantum optics, photonics and lasers, in particular non-equilibrium quantum dynamics of coupled light-matter systems. He is the recipient of the NSF CAREER Award and the DARPA Young Faculty Award.