  Room-temperature continuous-wave operation of InGaAs/AlGaAs quantum well
lasers directly grown on on-axis silicon (001) has been demonstrated. A 420 nm
thick GaAs epilayer completely free of antiphase domains was initially grown on
the silicon substrate in a metal-organic chemical vapor deposition system and
the other epilayers including four sets of five-period strained-layer
superlattices and the laser-structural layers were successively grown in a
molecular beam epitaxy system. The lasers were prepared as broad-stripe
Fabry-Perot ones with a stripe width of 21.5 um and a cavity length of 1 mm.
Typically, the threshold current and the corresponding threshold current
density are 186.4 mA and 867 A/cm2, respectively. The lasing wavelength is
around 980 nm and the slope efficiency is 0.097 W/A with a single-facet output
power of 22.5 mW at an injection current of 400 mA. This advancement makes the
silicon-based monolithic optoelectronic integration relevant to quantum well
lasers more promising with an enhanced feasibility.
