Concentration dependence of the refractive index for n - and p -type GaAs between 1.2 and 1.8 eV

Abstract

The refractive indices of GaAs at room temperature were determined from accurate double-beam reflectance measurements. The uncertainty in the refractive indices obtained by this technique is ±0.005. Measurements were made on high-purity n -type samples, n -type samples with free-electron concentrations from 5×1016 to 6.7×1018 cm−3, p -type samples with free-hole concentrations from 1.5×1016 to 1.6×1019 cm−3, and p -type samples heavily doped with the amphoteric impurity Si. These data agree with Marple's prism refractive data for both of his samples of the same impurity concentration. Analysis of the reflectance for the high-purity samples permitted assignment of the room-temperature energy gap as 1.424±0.001 eV. The shape of the refractive-index-vs-energy curve was found to be strongly dependent on the carrier concentration at energies near the direct energy gap.

Empirical model including band‐to‐band Coulomb interaction for refractive indices of GaAs and InP‐based materials at photon energies near and above the band‐gap

“…2(b) show the results of fitting our model to available GaAs data for absorption [7] and refractive index [8].The discrete exciton [2] is fitted by using the double-Lorentzian LSF. In GaAs, the light-hole band becomes quite nonparabolic after about 0.06 eV away from the valence-band maximum [15].…”

“…2 (a) The best fit of our absorption model to the experimental data for high-purity GaAs [7] in the 2 nd zone which yields a broadening parameter of 9.8 meV. (b) Comparison of the refractive-index spectrum obtained by our procedure and the experimental data [8].…”

Intrinsic Urbach Rule and Electron—Phonon Interaction in GaAs and Related III‐V Compounds

“…1. The data are corrected for reflectivity using the refractive index values reported in [17]. The absorption coefficient is well described by Urbach's rule, as staked in expression (I), with KO = 8 x 10l6 cm-l and hw, = 1.634 eV.…”

Analysis of mode behavior in a waveguide with graded index and gain

“…The free space wavelength of transmitted light ho was taken to be 0.84 pm. These values of ea and E , correspond to Alo~,,Ga,~,,As and Alo.,,Gao.65As as a material for an active layer and confinement layer [9] , [IO] .…”

“…[7] - [9] wasused [ 131. These lasers show impressive mode selectivity (high ratio of lasing to nonlasing mode intensities).…”