A project of the Theoretical Chemical and Quantum Physics Group


Dr. Jan Jeske, A/Prof. Jared Cole, Prof. Andrew Greentree


P. Longo: Heidelberg University

K. Busch: TU Berlin

Brief Project Outline

Quantum optics and condensed-matter are traditionally two separate branches of physics. The former being concerned with the interactions between atoms and photons, the latter with the effects of multi-particle systems in which local and non-local effects are observed. Recently, these two fields have started to overlap, resulting in such concepts as circuit-QED and quantum optics experiments in solid-state systems. We are interested in how quantum optics concepts can be implemented in solid-state systems as well as how condensed-matter effects can be observed in interacting atom-photon systems. Recent work includes:

  • The study of "solid-light", the prediction of Mott-Insulator type transitions in systems of coupled photonic cavities and strongly coupled atoms.
  • The propagation of excitations in nonlinear photonic cavity systems and their use in simulating classical and quantum optical elements.
  • The interaction of coherent and incoherent processes within a Jaynes-Cummings lattice system and the resulting correlated emission.

Phase diagram of a coupled-cavity system

Phase diagram of a Jaynes-Cummings lattice system, consisting of an array of coupled photonic cavities, each one strongly coupled to a two-level atom. The superfluid order parameter shows distinctive lobes which are charateristic of a Mott-Insulator/Superfluid quantum phase transition. In this case, this phase transition stems from the induced photon-photon interaction, via the atoms.
Greentree et al., Nature Physics 2, 856 - 861 (2006).

Excitation propagation in a coupled-atom-cavity array

Evolution of an initial excitation in a one-dimensional Jaynes-Cummings lattice consisting of 100 cavities. The atoms are detuned from the photonic cavities, resulting in a separation of velocities for the photonic and atomic excitations. The dashed lines are giving by an approximate analytic expression derived in the dispersive limit.
Makin et al., Phys. Rev. A 80, 043842 (2009).

Emission spectrum from an atom-cavity system

Fluorescence spectra of a laser-driven and dissipative two-cavity system resonant (top) and off-resonant (bottom) atom-photon coupling. The incoherent driving strength is adjusted such that the steady-state particle density is, 0.25, 0.5, 0.75 and 1.0. In addition to the spectra, the light gray (vertical) lines indicate single-particle excitations of the non-dissipative system from (0→1) excitation subspace transitions. These excitations yield the main contributions to the spectra.
Knap et al., Phys. Rev. A 83, 023821 (2011).

Recent Publications

M. Knap, E. Arrigoni, W. von der Linden, J. H. Cole Emission characteristics of laser-driven dissipative coupled-cavity systems, Phys. Rev. A 83, 023821 (2011)

M.I. Makin, Jared H. Cole, Charles D. Hill, Andrew D. Greentree, Lloyd C. L. Hollenberg Time evolution of the one-dimensional Jaynes-Cummings-Hubbard Hamiltonian, Phys. Rev. A 80, 043842 (2009)

A. D. Greentree, C. Tahan, J. H. Cole, L. C. L. Hollenberg Quantum phase transitions of light, Nature Physics, 2, 856 (2006)

For more information about this project, please contact Jared Cole or Andrew Greentree.