THE DIRECTIONALITY OF QUANTUM CONFINEMENT ON STRAIN-INDUCED QUANTUM-WIRE LASERS

Optical properties of Ga0.47-xIn0.53+xAs (x similar to 0.14) multiple- quantum-wire (MQWR) lasers prepared by the strain-induced lateral-laye r ordering process were studied. A typical ratio of threshold current density, similar to 10, was observed from the GaInAs MQWR lasers with contact stripes aligned to the [110] ([110] MQWR laser) and the [(1) o ver bar 10] ([(1) over bar 10] MQWR laser) directions. The threshold c urrent density of the [110] MQWR laser is similar to 30% lower than th at of a Ga0.47In0.53As multiple-quantum-well (MQW) reference laser. Th e 77 K lasing wavelengths were 1.46, 1.57, and 1.69 mu m for the MQW l aser, the [(1) over bar 10] and [110] MQWR lasers, respectively. This strong anisotropy of threshold current densities and lasing wavelength s is the first direct evidence of the directionality of two-dimensiona l quantum confinement in the MQWR structure. (C) 1998 American Institu te of Physics. [S0021-8979(98)08706-4].