Title :
Study on InGaAsP-InGaAs MQW-LD with symmetric and asymmetric separate confinement heterostructure
Author :
Duchang Heo ; Il Ki Han ; Jung Il Lee ; Jichai Jeong
Author_Institution :
Nano Device Res. Center, Korea Inst. of Sci. & Technol., Seoul, South Korea
Abstract :
We studied symmetric and asymmetric InGaAsP-InGaAs 1.55-μm multiquantum-well (MQW) laser diodes (LDs) with highly p-doped layers in the two-step separate confinement heterostructure (SCH). The p-doping in p-SCH suppresses the electron overflow from the MQWs to p-SCH, but it is an origin of free carrier absorption loss. An additional InGaAsP layer inserted inside n-SCH makes asymmetric field distribution and, therefore, reduces the portion of optical field distribution in highly p-doped regions with high optical loss. Compared with symmetric structure, asymmetric SCH LD has low threshold current density, low internal loss, and high and flat slope efficiency with respect to temperature.
Keywords :
III-V semiconductors; doping profiles; gallium arsenide; gallium compounds; indium compounds; optical losses; quantum well lasers; semiconductor quantum wells; 1.55 mum; InGaAsP-InGaAs; asymmetric separate confinement heterostructure; electron overflow; free carrier absorption loss; multiquantum-well laser diodes; optical field distribution; optical loss; p-doping; symmetric separate confinement heterostructure; Absorption; Carrier confinement; Diode lasers; Electron optics; Optical losses; Optical saturation; Optical waveguides; Quantum well devices; Temperature; Threshold current;
Journal_Title :
Photonics Technology Letters, IEEE
DOI :
10.1109/LPT.2004.829772
