Room temperature operation of 650 nm algaas multi-quantum-well laser diode grown by molecular beam epitaxy

Room temperature operation at a wavelength below 700 nm has been achieved by molecular beam epitaxially grown, modified multi-quantum-well structure laser diodes whose quantum well layers are composed of Al_xGa_1-xAs (x=0.15-0.35). These lasers have lower threshold current density than conventional double heterostructure lasers at a wavelength lower than 715 nm, and also lower value than the previouly reported MO-CVD grown single-quantum-well lasers at a wavelength lower than 690 nm. The shortest wavelength for pulse operation is 651.4 nm, whose value is the shortest among those reported so far on the room temperature AlGaAs laser diodes.