Temperature characteristics of tensile strained GaAs1-yPy-Al0.35Ga0.65As si
ngle quantum well heterostructure laser diodes are examined. The dependence
of the characteristic temperature (T-0) on the quantum well composition is
systematically studied in broad-area stripe lasers with identical quantum
well widths (115 Angstrom) and various cavity lengths. Laser diodes with 10
quantum well compositions ranging from y=0 (lattice matched) to 0.30 (simi
lar to 1.1% tensile strain) and 5 cavity lengths ranging from 300 to 1500 m
u m are examined. Characteristic temperatures are found to be maximized for
small (but generally nonzero) quantum well phosphorus compositions, with a
maximum value of T-0=159 K obtained for y=0.025, but decrease rapidly with
increasing composition. Our results are analyzed via a theoretical model f
or the characteristic temperature of the transparency current in separate c
onfinement quantum well lasers and comparison of our observations with othe
r measured laser characteristics. These analyses suggest that the observed
local maximum in T-0(y) at small y is a tensile strain effect, whereas the
decreased T-0(y) at large y results primarily from loss of carrier confinem
ent and barrier recombination. (C) 2000 American Institute of Physics. [S00
21-8979(00)02022-3].