Gain and Absorption Spectra of Quantum Wire Lasers Diodes Grown on Nonplanar Substrates
Abstract
Quantum wire (QWR) semiconductor lasers, grown by organometallic chemical vapor deposition OMCVD) on nonplanar substrates, exhibit two dimensional (2D) quantum confinement and sub-mA threshold currents. The in situ formation of the wires in these lasers eliminates excessive nonradiative recombination at their interfaces, which is essential for the efficient operation of these devices. One of the expected advantages of QWR heterostructures is the enhanced optical gain and absorption resulting from the increased density of states at the quasi-1D subbands. This feature would make QWR heterostructures useful for applications in low power consumption integrated optoelectronics. Here, we report the first measured gain and absorption spectra of QWR lasers. The multi-QWR lasers discussed here were grown by OMCVD on V- grooved substrates. Their active regions consist of 4 crescent-shaped GaAs wires, placed at the center of a 2D, graded index AlGaAs optical waveguide. A band structure model of these wires yields electron-heavy hole QWR subband transitions separated by 19meV, with an effective wire width of 15nm for the ground electron state, The subband structure was evident in the amplified spontaneous emission and lasing spectra of the devices, with observed transition energies in good agreement with the calculated values.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 1992
- Accession Number
- ADP008097
Entities
People
- A. Scherer
- D. M. Hwang
- E Kapon
- Huanyu Song
- M. Walther
- R. Bhat