Optical characteristics of p-type GaAs-based semiconductors towards applications in photoemission infrared detectors
- Department of Physics and Astronomy, Georgia State University, Atlanta, Georgia 30303 (United States)
- State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, P.O. Box 912, Beijing 100083 (China)
- School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore 639798 (Singapore)
Free-carrier effects in a p-type semiconductor including the intra-valence-band and inter-valence-band optical transitions are primarily responsible for its optical characteristics in infrared. Attention has been paid to the inter-valence-band transitions for the development of internal photoemission (IPE) mid-wave infrared (MWIR) photodetectors. The hole transition from the heavy-hole (HH) band to the spin-orbit split-off (SO) band has demonstrated potential applications for 3–5 μm detection without the need of cooling. However, the forbidden SO-HH transition at the Γ point (corresponding to a transition energy Δ{sub 0}, which is the split-off gap between the HH and SO bands) creates a sharp drop around 3.6 μm in the spectral response of p-type GaAs/AlGaAs detectors. Here, we report a study on the optical characteristics of p-type GaAs-based semiconductors, including compressively strained InGaAs and GaAsSb, and a dilute magnetic semiconductor, GaMnAs. A model-independent fitting algorithm was used to derive the dielectric function from experimental reflection and transmission spectra. Results show that distinct absorption dip at Δ{sub 0} is observable in p-type InGaAs and GaAsSb, while GaMnAs displays enhanced absorption without degradation around Δ{sub 0}. This implies the promise of using GaMnAs to develop MWIR IPE detectors. Discussions on the optical characteristics correlating with the valence-band structure and free-hole effects are presented.
- OSTI ID:
- 22596887
- Journal Information:
- Journal of Applied Physics, Vol. 119, Issue 10; Other Information: (c) 2016 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-8979
- Country of Publication:
- United States
- Language:
- English
Similar Records
Optical Pumping and Photoluminescence Detection of Spin-Polarized Electrons in Uniaxially Stressed Gallium Arsenide [Thesis]
Theory of optical spectra in a magnetic field in doped semiconductor quantum wells: Impurity-induced broadening and transitions
Related Subjects
GENERAL PHYSICS
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ABSORPTION
ALGORITHMS
ALUMINIUM ARSENIDES
CARRIERS
COOLING
DIELECTRIC MATERIALS
GALLIUM ARSENIDES
HOLES
INDIUM ARSENIDES
MAGNETIC SEMICONDUCTORS
PHOTODETECTORS
PHOTOEMISSION
P-TYPE CONDUCTORS
SPECTRAL RESPONSE
SPIN
VALENCE