Effects of well number, cavity length, and facet reflectivity on the reduction of threshold current of GaAs/AlGaAs multiquantum well lasers

• Published in: IEEE journal of quantum electronics Vol. 24; no. 4; pp. 635 - 640
• Main Authors: Kurobe, A., Furuyama, H., Naritsuka, S., Sugiyama, N., Kokubun, Y., Nakamura, M.
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.04.1988; Institute of Electrical and Electronics Engineers
• Subjects: Current density; Exact sciences and technology; Fundamental areas of phenomenology (including applications); Gallium arsenide; Lasers; Mirrors; Optical losses; Optical saturation; Optics; Physics; Quantum well devices; Quantum well lasers; Reflectivity; Semiconductor lasers; Semiconductor lasers; laser diodes; Threshold current; Gallium Arsenides; Length; Aluminium Gallium Arsenides Mixed; Multiple quantum well; Optical resonator; Face; Reflectance; Semiconductor laser; Threshold
• ISSN: 0018-9197; 1558-1713
• DOI: 10.1109/3.172

The optimum design for reducing the threshold current of GaAs/AlGaAs multiquantum well lasers is determined experimentally. The lowest threshold current density is realized by using single and multiquantum wells at long and short cavity lengths, respectively. The threshold current has a minimum at the optimum cavity length: the minimum threshold current is smaller for a larger number of quantum wells, and the optimum cavity length is inversely proportional to the number of wells. Experiments are compared to the theory developed by P.W.A. McIlroy, et al. (ibid., vol.21, no.12, p.1958-63, 1985) and limiting performances of quantum well lasers with various numbers of wells are presented. The reduction of the threshold current by high reflectivity coatings is also demonstrated, and a threshold current as low as 1.86 mA at 15 degrees C is reported.< >