A Comparison of Delayed Self-Heterodyne Interference Measurement of Laser Linewidth Using Mach-Zehnder and Michelson Interferometers

Sensors

Albert Canagasabey³  Andrew Michie³  John Canning³  John Holdsworth¹  Simon Fleming²  Hsiao-Chuan Wang³ 

[1] SMAPS, University of Newcastle, Callaghan, NSW 2308, Australia; E-Mail:;Institute of Photonics and Optical Science (IPOS), School of Physics, University of Sydney, 2006, NSW, Australia; E-Mail:;Interdisciplinary Photonics Laboratories (iPL), School of Chemistry, University of Sydney, 2006, NSW, Australia; E-Mails:

关键词: coherent optical effects;    heterodyne;    interferometry;    DFB;    laser linewidth;    faraday rotation;    Mach-Zehnder interferometer;    Michelson interferometer;    Gaussian noise;    Lorentzian noise;   

DOI  :  10.3390/s111009233

来源: mdpi

【 摘 要 】

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.

【 授权许可】

CC BY   
© 2011 by the authors; licensee MDPI, Basel, Switzerland.