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Abstract
Realising a platform for efficiently guiding and manipulating light at the singlephoton level lies at the heart of optical quantum information processing. In this thesis we aid in the pursuit of this goal by analysing fewphoton transport properties in photonic devices while keeping in mind possible applications and experimental challenges. We especially focus on single and twophoton transport properties in onedimensional waveguides coupled to (artificial) atoms modelled as two and threelevel emitters. We begin by introducing key concepts relevant for this thesis and then explain how to model such waveguide geometries. We show how directionaldependent coupling between a waveguide and a localized quantum system can be modelled from a chain of harmonic oscillators by allowing the system to couple to more than one site. Using the inputoutput formalism and scattering matrix theory we determine a general form for the single and twophoton Smatrices for a waveguide coupled to a twolevel system. We also explain how to engineer a quantum optical Fanoresonance waveguide geometry and calculate how this modifies the Smatrices,
the fewphoton scattering probabilities, and the scattered output spectra. We show that the nonlinear effects in such a system generates highly correlated directional scattering probabilities. We device a protocol that can generate maximal entanglement between two spectrally distinct solidstate emitters by the use of multiphoton scattering. The results also reveal a rich structure for multiphoton states interacting with nonidentical emitters. As a final investigation, we quantify how spectral diffusion in quantum dots affects finitewidth single and twophoton scattering. Singlephoton scattering probabilities are described by a simple convolution but this is not the case for a twophoton state scattering off a twolevel emitter. We show that the effect of spectral wandering depletes the nonlinear scattering properties, but that it affects co and counterpropagating output probabilities differently.
the fewphoton scattering probabilities, and the scattered output spectra. We show that the nonlinear effects in such a system generates highly correlated directional scattering probabilities. We device a protocol that can generate maximal entanglement between two spectrally distinct solidstate emitters by the use of multiphoton scattering. The results also reveal a rich structure for multiphoton states interacting with nonidentical emitters. As a final investigation, we quantify how spectral diffusion in quantum dots affects finitewidth single and twophoton scattering. Singlephoton scattering probabilities are described by a simple convolution but this is not the case for a twophoton state scattering off a twolevel emitter. We show that the effect of spectral wandering depletes the nonlinear scattering properties, but that it affects co and counterpropagating output probabilities differently.
Original language  English 

Publisher  Technical University of Denmark 

Number of pages  123 
Publication status  Published  2020 
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 1 Finished

An open quantum systems approach to few photon scattering in photonic devices
Joanesarson, K. B., Mork, J., Gregersen, N., IlesSmith, J., Rottwitt, K., Tufarelli, T., Rotenberg, N. & Heuck, M.
01/02/2017 → 06/05/2020
Project: PhD