Near-ideal low threshold behavior in (111) oriented GaAs/AlGaAs quantum well lasers

Abstract

Fundamental characteristics of (111) oriented GaAs/AlGaAs graded-index separate-confinement-heterostructure single quantum well lasers have been compared with conventional (100) oriented lasers. In particular, the threshold current density Jth of (111) oriented lasers does not change with the well width Lz in the range of Lz=30–100 Å, which corresponds to an ideal extreme. The lowest Jth of 145 A/cm2 together with a high characteristic temperature T0 of 186 K in the threshold-temperature dependence has been achieved for an Lz of 40 Å and a cavity length of 490 μm. The dependence of T0 on Lz showed that T0 is maximum at Lz∼60 Å for both (111) and (100) oriented lasers.

Gradual degradation in InAs quantum dot lasers on Si and GaAs

“…These factors have been shown to strongly influence degradation rates of GaAs quantum well and double heterostructure lasers. 30,31 Both these and QD lasers contain GaAs in or near the active region and may share a common degradation mechanism, so further optimization should benefit QD lasers. Recent collaborations have demonstrated, via DLTS measurements, that QD lasers on silicon and GaAs share a common hole trap associated with a native point defect species or an oxygen complex.…”

First principles calculation of the opto-electronic properties of (110) growth axis SiGe superlattices

“…To our knowledge, the problem of SL's with various growth axis directions has been often addressed by means of the envelope function approach in the past [23][24][25][26][27][28][29][30][31][32] and rarely by other methods such as the tight binding approach [33] or the first principles methods. The present first principles approach is free from adjustable parameters and is able to contribute to shedding light on different aspects of the problem.…”

Molecular-beam epitaxy growth of quantum cascade lasers on (111)B substrates for second harmonic generation

“…Some attempts have been made on surfaces with high Miller's indices ͓͑111͒, ͑211͒,...͔ to take advantage of the band structure anisotropy 2,3 or to exploit the piezo-electricity 4 of the III-V materials. For this reason, most of the III-V devices have been grown and optimized on ͑100͒ oriented substrates.…”