title: Tailored first- and second-order coherence properties of quantum dot superluminescent diodes via optical feedback.
abstract: We demonstrate experimentally that the first- and second-order coherence properties of light emitted by a quantum dot superluminescent diode can be simultaneously tailored by well-controlled optical feedback. Depending on feedback intensity and feedback spectral range we achieve a spectral width Δλ between 120 and 0.26 nm, corresponding to a coherence length in first order in the range between 13 and 5820 μm, while the central second-order coherence degree g((2))(τ=0) is tuned gradually from a thermal value of g((2))(0)~1.8 down to the coherent laser limit of g((2))(0)=1.0. These results are complemented by comprehensive investigations of relative intensity noise, which are in excellent agreement with the observed intensity correlation behavior.
authors.affiliation: Institute of Applied Physics, Technical University Darmstadt, Schlossgartenstr. 7, 64289 Darmstadt, Germany. sebastien.hartmann@physik.tu‑darmstadt.de
authors.forename: Sébastien
authors.initials: S
authors.lastname: Hartmann
authors.forename: Andreas
authors.initials: A
authors.lastname: Molitor
authors.forename: Martin
authors.initials: M
authors.lastname: Blazek
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Elsässer
mesh_terms: D005246:Feedback; D008027:Light; D049449:Luminescence; D061848:Optical Imaging; D055620:Optical Phenomena; D045663:Quantum Dots; D012666:Semiconductors