Quantum cascade laser wavelength tuning due to temperature-dependent index of refraction

Author

Ahmed, Arif ; Hassan, O. ; Sohel, Md S. H. ; Hayee, F. ; Faria, Rafael ; Talukder, Muhammad Anisuzzaman

Author_Institution

Dept. of Electr. & Electron. Eng., Bangladesh Univ. of Eng. & Technol., Dhaka, Bangladesh

fYear

2012

fDate

13-16 Dec. 2012

Firstpage

1

Lastpage

5

Abstract

In this work, we study the change in the emission wavelength of quantum cascade lasers when the index of refraction of the lasing medium changes due to a change in the temperature. We find that the gain of the laser and the wavelength of the longitudinal optical modes in the laser cavity change significantly as the temperature changes. As a result, the output wavelength of QCLs changes as the temperature changes. When the wavelength of the lasing mode changes so much that one of the neighboring modes becomes the closest mode to the peak of the gain spectrum, the lasing hops to the neighboring mode. We also find that the mode-tuning and mode-hopping depend on the longitudinal length of the laser cavity. The tuning range increases for a smaller cavity, while the mode-hopping becomes more frequent for a longer cavity as the temperature increases.

Keywords

laser cavity resonators; laser modes; laser tuning; quantum cascade lasers; refractive index; QCL; emission wavelength; gain spectrum; laser cavity longitudinal length; lasing medium; lasing mode-hopping; lasing mode-tuning; longitudinal optical modes; quantum cascade laser wavelength tuning; temperature-dependent refraction index; Cavity resonators; Indexes; Laser modes; Quantum cascade lasers; Scattering; Tuning; Electron Scattering; Emission Wavelength; Index of Refraction; Peak Modal Gain; Quantum Cascade Laser;

fLanguage

English

Publisher

ieee

Conference_Titel

Photonics Global Conference (PGC), 2012

Conference_Location

Singapore

Print_ISBN

978-1-4673-2513-4

Type

conf

DOI

10.1109/PGC.2012.6457941

Filename

6457941