The effect of interface pond configuration on the structural and optical properties of short-period ( ~5 0 A) GaSb/lnAs superlattices has been examined. Structures consisting of eight monolayers of GaSb and seven monolayers of lnAs with either 'GaAs-like' or 'InSb-like' interface bonds were grown by MBE. Evidence for differences in the Structural properties, vibrational properties and band srrucrure or me two rypes 01 mareriai was omaineo usiny x-ray uimraciiuri, Raman scattering, interband magneto-absorption and ohotoconductivitv measurements.

InAs/Ga1−xInxSb superlattices have been investigated by magneto-optical and magnetotransport techniques. Band gaps, determined from interband magneto-optical measurements and from the temperature dependence of the intrinsic carrier concentration, are in the long wavelength infrared region (8.3–12.4 μm) and are in good agreement with gaps calculated from a two-band model. Both electron and hole effective masses were measured by cyclotron resonance and the electron effective mass is found to be a factor of 4–5 larger than in HgCdTe (the industry standard IR material). This is necessary for reduced dark currents and good optical absorption coefficients in this material.

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We have carried out infrared magnetotransmission measurements on a 5000-A-thick bismuth film grown by molecular beam epitaxy onto a CdTe substrate. The data for photon energies below 300 meV display at least ten orders of minima due to interband transitions at the L points. In contrast to previous results from magnetore8ectivity experiments on bulk Bi, two concurrent series of resonances separated by a nearly constant energy of 5 meV are observed. An additional series of strong oscillations emerges at somewhat higher photon energies, due to interband transitions at the T point. The energy dispersion of these resonances are fit quite well by a simple nonparabolic model, allowing us to directly determine the T-point energy gap (407 meV) and the electron-hole reduced mass (0.027mo, which implies an electron mass of 0.048mo).

Absiract. InAs/Ga,-,ln,Sb superlattices have been investigated by magnetooptical and magnetotransport techniques. Bandgaps, determined from interband magneto-optical measurements and from the temperature dependence of the intrinsic carrier concentration, are in the long-wavelength inirared region (8.3 to 12.4 pm) and are in good agreement with gaps calculated from a two-band model, Both electron and hole effective masses were measured by cyclotron resonance and the electron effective mass is found to be a factor of 4-5 times larger than In HgCdTe (the industry-standard IR material). This is necessary for reduced dark currents and good optical absorption coefficients in this material. Finally, the first observation of higher-order electron and hole subbands (bv interband magneto-optics) in this material system is reported