Research on long wavelength bias-assisted photoemitters
Abstract
The infrared threshold for photoemission has been extended to 2.1 microns by use of a bias-assisted lattice-mismatched In.77Ga.23As/InAsP/InP photocathode. Quantum yield at 1.9 microns was .002 electrons/incident photon, for 2.4V bias and a temperature of approximately 125K. This photocathode structure was grown by vapor phase epitaxy. Molecular beam epitaxy (MBE) has also been used to grow In.77Ga.23As/buffer/InP structures. The effect of different buffer layer schemes, including a superlattice structure, on MBE-grown In.77Ga.23As mobility and photoluminescence was investigated. Infrared imaging was demonstrated out to 1.65 microns using an In.53Ga.47As/InP bias-assisted photocathode operating in the transmission mode. Good reduction and sensitivity were obtained, indicating the potential usefulness of bias-assisted photocathodes for infrared imaging.
- Publication:
-
Final Report
- Pub Date:
- October 1981
- Bibcode:
- 1981vara.reptQ....G
- Keywords:
-
- Infrared Imagery;
- Long Wave Radiation;
- Photoelectric Emission;
- Photoelectric Materials;
- Vapor Phase Epitaxy;
- Crystal Lattices;
- Electron Transfer;
- Indium Compounds;
- Photocathodes;
- Photoluminescence;
- Research And Development;
- Solid-State Physics