Properties of Spontaneous and Stimulated Emission in GaAs Junction Lasers. I. Densities of States in the Active Regions
- 15 November 1970
- journal article
- research article
- Published by American Physical Society (APS) in Physical Review B
- Vol. 2 (10) , 4117-4125
- https://doi.org/10.1103/physrevb.2.4117
Abstract
The densities of states in the conduction and valence bands appropriate for the region of the junction have been calculated self-consistently in the screened potential and effective-mass approximations. Such a density of states for one particular band consists of a tail part taken from the theory of Halperin and Lax, an unperturbed parabolic density of states above the tail, and a smooth interpolation in between. The use of the unperturbed parabolic band is justified, since the perturbation technique of Bonch-Bruevich and a straightforward second-order perturbation calculation both show that the distortion of the band due to the presence of impurities at the concentration employed in a typical laser is less than 5%. Contrary to the generally accepted assumption and Stern's calculation using Kane's density of states of a long and reasonable large conduction band tail, our results show that the tail is negligibly small compared to the valence band tail. On the basis of this calculation, it is concluded that, for a typical laser, the electron quasi-Fermi level at lasing threshold for temperature above 77 °K should be in the parabolic portion of the band and not in the tail as is often assumed without justification. The approximations of using linear screening for the impurity potentials and the Gaussian statistics for the impurity distribution which are implied in the density-of-state functions of Kane and of Halperin and Lax are considered in detail.
Keywords
This publication has 21 references indexed in Scilit:
- Analysis of Population Inversion for Lasing Threshold in SemiconductorsJapanese Journal of Applied Physics, 1968
- Lasing wavelength of a GaAs injection laserSolid-State Electronics, 1968
- Spontane und induzierte Emission in LaserdiodenThe European Physical Journal A, 1967
- Spontane und induzierte Emission in LaserdiodenThe European Physical Journal A, 1967
- Impurity-Band Tails in the High-Density Limit. I. Minimum Counting MethodsPhysical Review B, 1966
- Effect of Band Tails on Stimulated Emission of Light in SemiconductorsPhysical Review B, 1966
- Spontaneous and Stimulated Recombination Radiation in SemiconductorsPhysical Review B, 1964
- Optical Transitions Involving Impurities in SemiconductorsPhysical Review B, 1963
- Coherent light emission from p-n junctionsSolid-State Electronics, 1963
- Thomas-Fermi Approach to Impure Semiconductor Band StructurePhysical Review B, 1963