Abstract
GaInP-AlGaInP strained quantum-well lasers with emission wavelength at 630-nm band are theoretically analyzed in detail and then optimized. The valence band structure of quantum wells is obtained by evaluating the 6×6 Luttinger-Kohn Hamiltonian including the coupling among the heavy hole, the light hole, and the spin-orbital split-off hole bands. The effect of optical transition from/to continuum states not confined to the quantum well is studied. It is found that the optical transition from/to the continuum states is serious as the band gap of the confining layers is close to the quasi-Fermi level separation, leading to considerable radiative current This radiative current is undesirable since the corresponding optical transition does not contribute significantly to the threshold gain. The gain-radiative current characteristic is therefore poor for confining layers containing a low Al content To avoid unreasonable gain/absorption, the non-Markovian convolution lineshape is used instead of the conventional Lorentzian lineshape. The leakage current is high for single quantum-well lasers with wide bandgap confining layers. It can be reduced by increasing the quantum-well number, the dopant concentration, and the band gap of cladding layers. The calculated threshold current agrees well with the observation. The band gap shrinkage due to the carrier-carrier interaction is considered to obtain an emission wavelength consistent with the experimental result.
Original language | English |
---|---|
Pages (from-to) | 443-456 |
Number of pages | 14 |
Journal | IEEE Journal of Quantum Electronics |
Volume | 33 |
Issue number | 3 |
DOIs | |
State | Published - Mar 1997 |
Keywords
- Quantum well lasers
- Quantum wells
- Semiconductor device modeling
- Semiconductor lasers
- Spontaneous emission
- Visible lasers