Premium
Optically Injection‐Locked Mid‐IR Quantum‐Cascade Lasers: The Output‐Power–Modulation‐Bandwidth–Noise Trilogy
Author(s) -
Sheikhey Mohammad M.,
Yadipour Reza,
Baghban Hamed
Publication year - 2018
Publication title -
annalen der physik
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.009
H-Index - 68
eISSN - 1521-3889
pISSN - 0003-3804
DOI - 10.1002/andp.201800079
Subject(s) - optics , laser , relative intensity noise , physics , bandwidth (computing) , quantum cascade laser , injection locking , cascade , semiconductor laser theory , modulation (music) , materials science , optoelectronics , computer science , telecommunications , acoustics , chemistry , chromatography
A comprehensive study on the output power, the modulation response, and the relative intensity noise (RIN) behavior of an optically injection‐locked mid‐infrared quantum‐cascade laser reveals that the modulation bandwidth and the output power are enhanced in the stable locking range, while the RIN of the slave laser is a superposition of the master and slave noise sources. Since the RIN level of the master laser can even take the lead, a design procedure is introduced to improve the main characteristics of a free‐running laser, including the RIN, the photon lifetime, the modulation bandwidth, and the bias current, using facet reflectivity tailoring. A figure of merit is defined and the RIN reduction of about 20 dB Hz −1 is obtained for very low injection powers compared with the injection‐locked system before the design of master laser.