Open AccessInP-based quantum cascade lasers monolithically integrated onto silicon
Author(s) -
Rowel Go,
Hubert Krysiak,
Matthew Fetters,
Pedro Figueiredo,
Matthew Suttinger,
X. M. Fang,
A. Eisenbach,
J. M. Fastenau,
D. Lubyshev,
A W K Liu,
N G Huy,
Aled Morgan,
Simon Edwards,
Mark J. Furlong,
Arkadiy Lyakh
Publication year - 2018
Publication title -
optics express
Language(s) - Uncategorized
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.26.022389
Subject(s) - materials science , lasing threshold , laser , optoelectronics , quantum cascade laser , silicon , cascade , optics , substrate (aquarium) , semiconductor laser theory , waveguide , quantum well , wavelength , semiconductor , physics , chemistry , oceanography , chromatography , terahertz radiation , geology
Lasing is reported for ridge-waveguide devices processed from a 40-stage InP-based quantum cascade laser structure grown on a 6-inch silicon substrate with a metamorphic buffer. The structure used in the proof-of-concept experiment had a typical design, including an Al 0.78 In 0.22 As/In 0.73 Ga 0.27 As strain-balanced composition, with high strain both in quantum wells and barriers relative to InP, and an all-InP waveguide with a total thickness of 8 µm. Devices of size 3 mm x 40 µm, with a high-reflection back facet coating, emitted at 4.35 µm and had a threshold current of approximately 2.2 A at 78 K. Lasing was observed up to 170 K. Compared to earlier demonstrated InP-based quantum cascade lasers monolithically integrated onto GaAs, the same laser structure integrated on silicon had a lower yield and reliability. Surface morphology analysis suggests that both can be significantly improved by reducing strain for the active region layers relative to InP bulk waveguide layers surrounding the laser core.