Optical self-pulsation behavior of cw (AlGa)As shallow proton-bombarded and narrow-striped (5 μm) double-heterostructure lasers grown by molecular beam epitaxy

A statistical study of the self-induced pulsation behavior of cw (AlGa)As double-heterostructure (DH) (having Al0.08Ga0.92 As active layers) proton-bombarded stripe lasers grown by molecular beam epitaxy (MBE) during accelerated aging at elevated (55 or 70 °C) temperatures is made and compared with that of similar lasers grown by liquid-phase epitaxy (LPE). For the 5-μm-stripe, shallow proton-bombarded (proton damage does not reach the active layer) stripe lasers, those fabricated from an MBE DH wafer studied show a significantly higher oscillation frequency (Fosc) of the self-pulsation than those fabricated from LPE DH wafers. It is also shown that by going from 10-μm-stripe and deep proton-bombarded (proton damage penetrates the active layer) to 5-μm-stripe and shallow proton-bombarded stripe lasers, the Fosc are significantly higher even after an initial burn-in at elevated temperatures (55 or 70 °C) for 100 h.