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Abstract
This thesis concerns the theoretical investigation of interference phenomena related to elastic and inelastic scattering of quantized light. The presented work is naturally divided into two parts, the first is concerning elastic scattering while the second explores inelastic scattering. In the first part we use a scatteringmatrix formalism combined with results from randommatrix theory to investigate the interference of quantum optical states on a multiple scattering medium. We investigate a single realization of a scattering medium thereby showing that it is possible to create entangled states by interference of squeezed beams. Mixing photon states on the single realization also shows that quantum interference naturally arises by interfering quantum states. We further investigate the ensemble averaged transmission properties of the quantized light and see that the induced quantum interference survives even after disorder averaging. The quantum interference manifests itself through increased photon correlations. Furthermore, the theoretical description of a measurement procedure is presented. In this work we relate the noise power spectrum of the total transmitted or reflected light to the photon correlations after ensemble averaging. This analysis enables us to describe an experimental observation of the quantum nature of light that survives the averaging over disorder. In the second part we investigate inelastic scattering. This we do by first treating the scattering of light on dipoles embedded in an arbitrary dielectric environment. By considering the two different models for dipole interaction known as the minimalcoupling and electricdipole interaction Hamiltonians, we find exact relations between the electric field and the dipole operators in the Heisenberg picture, while keeping the model of the dipoles arbitrary. Due to the exact treatment of the electricfield operators, we obtain kernels known from classical scattering theory to describe the propagation of the field from the dipoles. Using the found electric field operators we derive the Heisenberg equations of motion for the dipoles while treating them as quantum twolevel systems and using the Born–Markov and rotatingwave approximations. Postponing the rotatingwave approximation to the very end of the formal calculations allows us to identify the different physical parameters of the dipole evolution in terms of physical quantities known from optics. Finally, we use our Heisenberg picture formalism to treat a dilute cloud of twolevel atoms, by simplifying the equations of motion using a singlescattering approximation for the interaction between the atoms. This enables us to derive expressions for the steadystate population and fluorescence spectrum, where we find cooperative effects in both the elastic and the inelastic spectra.
Original language  English 

Place of Publication  Kgs. Lyngby 

Publisher  Technical University of Denmark 
Number of pages  126 
Publication status  Published  2012 
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Dive into the research topics of 'Quantum Optical Multiple Scattering'. Together they form a unique fingerprint.Projects
 1 Finished

Quantum optical properties of metamaterials
Ott, J. R. (PhD Student), Mortensen, N. A. (Main Supervisor), Lodahl, P. (Supervisor), Wubs, M. (Supervisor), Brandbyge, M. (Examiner), Mosk, A. P. (Examiner) & Mølmer, K. (Examiner)
01/04/2009 → 22/06/2012
Project: PhD