Spatial Characterization Of Two-Photon States - GAP-Optique

Introduction
the transfer of oam from the generating pump beam to the down-converted
photons. Several studies have reported a compleate transfer of the oam of the
pump [7, 8, 22, 27, 28, 29], while other studies have reported a partial transfer
[30, 31, 32, 33]. The elucidation of the oam spectra of down-converted photons,
and their relation with the spectra of the pump, is a key step for developing
new applications based on this degree of freedom.
This thesis addresses the mentioned oam controversy, as well as the characterization
of the different correlations present in two-photon states. For both
processes, spdc and Raman transitions in cold atoms, this thesis describes the
generated two-photon state, the correlations between different degrees of freedom
and between photons, and the oam transfer. A general goal of the thesis
is to contribute to the characterization of the two-photon sources, making it
possible to exploit a bigger portion of the total quantum state of the light in
future applications.
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