Lateral current injection distributed feedback laser with wirelike active regions

One of the promising candidates to solve a problem of a performance limitation of LSI is replacing the electrical global wiring by an on chip optical interconnection. A semiconductor membrane laser, which consists of a high-index contrast waveguide, is expected to operate with ultra low threshold current due to an enhanced modal gain. We have introduced a lateral current injection (LCI) structure for electrically pumped membrane laser, and demonstrate LCI type Distributed feedback (DFB) laser with wirelike active region prepared on a semi-insulating (SI) InP substrate. A threshold current of as low as 11 mA and a stable single-mode operation were obtained for a device with the stripe width of 1.5 μm and the cavity length of 300 μm under a room-temperature continuous-wave (RT-CW) condition.