Laser diode linewidth measurement using high-Q spherical microresonators

Author

Pineda-Vadillo, P. ; Lynch, M. ; Charlton, C. ; Tessarin, S. ; Donegan, J.F. ; Weldon, V.

Author_Institution

Semicond. Photonics Group, Trinity Coll., Dublin, Ireland

Volume

47

Issue

2

fYear

2011

fDate

1/1/2011 12:00:00 AM

Firstpage

129

Lastpage

130

Abstract

A novel technique to measure the emission linewidth of laser diodes (LDs) utilising whispering gallery modes (WGMs) in high-Q microspheres (diameter≃200μm) is proposed and demonstrated. Laser light from a distributed feedback (DFB) LD operating at λ≃1537.1nm is coupled into silica glass microspheres of Q≃10⁷ (estimated experimentally). WGM spectra are recorded and then used to estimate the DFB LD emission linewidth, yielding a value of 3.8 MHz. The estimated value is in good agreement, within experimental error, with a linewidth value of 6.0 MHz independently measured using the self-homodyne technique, strongly supporting the validity of this novel method.

Keywords

distributed feedback lasers; micromechanical resonators; semiconductor lasers; whispering gallery modes; DFB LD emission linewidth; WGM spectra; distributed feedback; frequency 3.8 MHz; frequency 6 MHz; high-Q spherical microresonators; laser diode linewidth measurement; self-homodyne technique; whispering gallery modes;

fLanguage

English

Journal_Title

Electronics Letters

Publisher

iet

ISSN

0013-5194

Type

jour

DOI

10.1049/el.2010.2739

Filename

5700015