title: Measurement and modification of biexciton-exciton time correlations.
abstract: Photons which are generated in a two-photon cascade process have an underlying time correlation since the spontaneous emission of the upper level populates the intermediate state. This correlation leads to a reduction of the purity of the photon emitted from the intermediate state. Here we characterize this time correlation for the biexciton-exciton cascade of an InAs/GaAs quantum dot. We show that the correlation can be reduced by tuning the biexciton transition in resonance to a planar distributed Bragg reflector cavity. The enhanced and inhibited emission into the cavity accelerates the biexciton emission and slows down the exciton emission thus reduces the correlation and increases the purity of the exciton photon. This is essential for schemes like creating time-bin entangled photon pairs from quantum dot systems.
authors.affiliation: Institute for Experimental Physics, University of Innsbruck, Technikerstrasse 25, 6020 Innsbruck, Austria. tobias.huber@uibk.ac.at
authors.forename: Tobias
authors.initials: T
authors.lastname: Huber
authors.forename: Ana
authors.initials: A
authors.lastname: Predojević
authors.forename: Hashem
authors.initials: H
authors.lastname: Zoubi
authors.forename: Harishankar
authors.initials: H
authors.lastname: Jayakumar
authors.forename: Glenn S
authors.initials: GS
authors.lastname: Solomon
authors.forename: Gregor
authors.initials: G
authors.lastname: Weihs
mesh_terms: D004867:Equipment Design; D019544:Equipment Failure Analysis; D017785:Photons; D045663:Quantum Dots; D012031:Refractometry / Q000295:instrumentation*; D012542:Scattering, Radiation; D013223:Statistics as Topic