Shallow to deep transformation of Se donors in GaSb under hydrostatic pressure

Journal Article · Mon Mar 01 04:00:00 EST 1999 · Physical Review, B: Condensed Matter

DOI:https://doi.org/10.1103/PhysRevB.59.8003· OSTI ID:341176

Navarro-Contreras, H; de Anda-Salazar, F; Olvera-Hernandez, J ^[1]; Hsu, L; McCluskey, M D ^[2]; Haller, E E ^[3]

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1. Instituto de Investigacion en Comunicacion Optica, Universidad Autonoma de San Luis Potosi, Alvaro Obregon 64, San Luis Potosi, S.L.P., (Mexico) 78000
2. Department of Physics, University of California, Berkeley, California 94720 (United States)
3. Center for Advanced Materials, Materials Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States)

We have observed that highly doped GaSb:Se, which is opaque to far IR radiation, becomes transparent at hydrostatic pressures above 9.8{plus_minus}2&hthinsp;kbar. We discuss how this behavior may be explained by the transformation of Se shallow donors into Se-DX (where DX is the unknown donor or X donor) centers in GaSb. Under this assumption the position of the Se-DX energy level at zero pressure is calculated to lie 80{plus_minus}30 meV above the conduction band at atmospheric pressure. The onset of transparency allowed us to observe several multiphonon absorbance features. We assign six of them to two-phonon absorptions. From the measured pressure dependence of the TO phonon, the Gr{umlt u}neisen parameter for this compound is calculated to be {gamma}{sub TO}=1.23{plus_minus}0.18. No persistent photoconductivity is observed for these Se-DX centers, a fact that may be explained by the expectation that the optical energy necessary to transform them back into the shallow form is larger than the band-gap energy of GaSb at all pressures examined, although it may be also an indication that the Se shallow donors change to deep donors associated with the L{sub 1} minima of ionization energy larger than 90 meV. {copyright} {ital 1999} {ital The American Physical Society}

• OSTI ID: 341176
• Journal Information: Physical Review, B: Condensed Matter, Journal Name: Physical Review, B: Condensed Matter Journal Issue: 12 Vol. 59; ISSN 0163-1829; ISSN PRBMDO
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
DOPED MATERIALS
GALLIUM ANTIMONIDES
GALLIUM COMPOUNDS
GRUENEISEN CONSTANT
IMPURITIES
INFRARED RADIATION
INFRARED SPECTRA
OPACITY
PHASE TRANSFORMATIONS
PHOTOCONDUCTIVITY
PRESSURE DEPENDENCE
SELENIUM
SELENIUM ADDITIONS
VERY HIGH PRESSURE