Title :
60ps recovery time in an InGaAsP quaternary multiple quantum well saturable absorber employing carrier sweep-out
Author :
Burr, E.P. ; Song, J. ; Seeds, A.J. ; Button, C.C.
Author_Institution :
Dept. of Electron. & Electr. Eng., Univ. Coll. London, UK
Abstract :
Summary form only given. Carrier sweep-out as a fast recovery mechanism has previously been investigated in a range of multiple quantum well (MQW) saturable absorbers (SA). We describe a PIN SA incorporating InGaAsP quaternary wells and barriers, lattice matched to InP which can be used as a reflective saturable absorber at wavelengths in the erbium gain window and present the first sweep-out in such a device. The MQW incorporates 60 wells to increase the contrast ratio under saturation and due to the quaternary structure presents low barriers to free carriers in both the conduction band and valence band wells to facilitate sweep-out. A distributed Bragg reflector (DBR) designed for operation at 1545 nm is positioned below the MQW region allowing reflective operation. The DBR and MQW are grown on an n/sup +/ substrate in a single MOVPE step. Devices are fabricated as 100 /spl mu/m diameter mesa structures with anti-reflection coating to suppress Fabry-Perot effects.
Keywords :
III-V semiconductors; MOCVD; antireflection coatings; gallium arsenide; gallium compounds; indium compounds; laser accessories; optical fabrication; optical materials; optical saturable absorption; quantum well devices; semiconductor quantum wells; vapour phase epitaxial growth; 1545 nm; 60 ps; Fabry-Perot effects; InGaAsP; InGaAsP quaternary barriers; InGaAsP quaternary multiple quantum well saturable absorber; InGaAsP quaternary wells; InP; MQW region; PIN saturable absorber; anti-reflection coating; carrier sweep-out; conduction band; contrast ratio; distributed Bragg reflector; erbium gain window; fabricated devices; fast recovery mechanism; free carriers; mesa structures; multiple quantum well saturable absorbers; quaternary structure; recovery time; reflective operation; reflective saturable absorber; single MOVPE step; valence band wells; High speed optical techniques; Nonlinear optics; Optical beams; Optical mixing; Optical modulation; Optical polarization; Optical signal processing; Semiconductor optical amplifiers; Stimulated emission; Switches;
Conference_Titel :
Lasers and Electro-Optics Europe, 2000. Conference Digest. 2000 Conference on
Conference_Location :
Nice
Print_ISBN :
0-7803-6319-1
DOI :
10.1109/CLEOE.2000.909771
