Electronic Resource
[S.l.]
:
American Institute of Physics (AIP)
Journal of Applied Physics
91 (2002), S. 4904-4909
ISSN:
1089-7550
Source:
AIP Digital Archive
Topics:
Physics
Notes:
Photoreflectance (PR) measurements have been carried out to determine the E0 and E0+Δ0 critical-point (CP) parameters in GaP at temperatures between 12 and 300 K using a He–Cd laser as modulation light source. The measured PR spectra provide distinct structures at ∼2.75–2.85 eV (E0) and ∼2.85–2.95 eV (E0+Δ0). These structures are successfully explained by a three-dimensional (3D) one-electron line shape plus an excitonic shape. The temperature dependence of the 3D CP and excitonic parameters (energy, amplitude, and broadening parameter) have been determined and analyzed using the Varshni equation and an empirical expression of Bose–Einstein type. The rapid decrease in the PR signal amplitudes is observed at T〈100 K and can be explained by the weakened surface electric fields due to carrier freezing at such low temperatures. The 3D exciton binding energy at the E0/(E0+Δ0) edges of GaP has also been determined to be 13 meV. © 2002 American Institute of Physics.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.1461067
Permalink
| Library |
Location |
Call Number |
Volume/Issue/Year |
Availability |
