title: A comparison of delayed self-heterodyne interference measurement of laser linewidth using Mach-Zehnder and Michelson interferometers.
abstract: Linewidth measurements of a distributed feedback (DFB) fibre laser are made using delayed self heterodyne interferometry (DHSI) with both Mach-Zehnder and Michelson interferometer configurations. Voigt fitting is used to extract and compare the Lorentzian and Gaussian linewidths and associated sources of noise. The respective measurements are w(L) (MZI) = (1.6 ± 0.2) kHz and w(L) (MI) = (1.4 ± 0.1) kHz. The Michelson with Faraday rotator mirrors gives a slightly narrower linewidth with significantly reduced error. This is explained by the unscrambling of polarisation drift using the Faraday rotator mirrors, confirmed by comparing with non-rotating standard gold coated fibre end mirrors.
authors.affiliation: Interdisciplinary Photonics Laboratories, School of Chemistry, University of Sydney, 2006, NSW, Australia. albert.canagasabey@sydney.edu.au
authors.forename: Albert
authors.initials: A
authors.lastname: Canagasabey
authors.forename: Andrew
authors.initials: A
authors.lastname: Michie
authors.forename: John
authors.initials: J
authors.lastname: Canning
authors.forename: John
authors.initials: J
authors.lastname: Holdsworth
authors.forename: Simon
authors.initials: S
authors.lastname: Fleming
authors.forename: Hsiao-Chuan
authors.initials: HC
authors.lastname: Wang
authors.forename: Mattias L
authors.initials: ML
authors.lastname: Aslund
mesh_terms: D005246:Feedback; D007368:Interferometry / Q000295:instrumentation*; D007834:Lasers; D016011:Normal Distribution; D055095:Optics and Photonics; D009991:Oscillometry; D013997:Time Factors