We introduce two simple methods, a current scanning method and a reflectivity scanning method, for measuring the linewidth enhancement factor (α) in an external cavity laser diode (ECLD). Both methods utilize the functional relationship associated with α between the emission wavelength and effective reflectivity of the compound cavity of ECLD. The change of emission wavelength as a function of an injection current and of an external reflectivity is used to determine the value of α in the current scanning method and in the reflectivity scanning method, respectively. The measured values of α by the two methods showed a fairly good agreement.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Atomic and Molecular Physics, and Optics
- Physical and Theoretical Chemistry
- Electrical and Electronic Engineering