Title of article :
ENHANCED EFFICIENCY OF GAAS-GA_x AL_1-x AS LASER WITH /4 ANTIREFLECTIONS COATING OF TIO_2 THIN FILMS: AN OPTICAL ENGINEERING
Author/Authors :
Riaz, K. N. Bahauddin Zakariya University - Department of Physics, Pakistan , Ullah, H. Bahauddin Zakariya University - Department of Physics, Laser and Optronics Laboratory, Pakistan , Khalid, S. Bahauddin Zakariya University - Department of Physics, Pakistan , Malik, A. S. Bahauddin Zakariya University - Department of Electrical Engineering, Pakistan , Ahmed, E. Bahauddin Zakariya University - Department of Physics, Pakistan
Abstract :
Titanium dioxide (TiO2) dielectric material was deposited as ~/4 antireflections (AR) coating 2 on one facet of GaAs-Ga_x Al_1-x As double hetero-structure (DH) laser. Single layer ~ /4 AR coating was achieved by successive deposition of TiO_2 thin films in vacuum in small steps by thermal evaporation technique, while measuring the threshold current after each coating outside the vacuum. Threshold current, reflectivity and far-field patterns of laser show the significant influence of AR coatings on light output characteristics. Internal loss parameter and the gain coefficient for the DH laser were determined from threshold current under the case temperature of the laser.
Keywords :
Semiconductor lasers , antireflection coatings , thin films , hetero , structure
Journal title :
Journal of Faculty of Engineering and technology (JFET)
Journal title :
Journal of Faculty of Engineering and technology (JFET)
