We report far-infrared reflectivity measurements on (GaAs)m/(AlAs)n superlattices (SL's) with systematically varied layer thicknesses in the range 1 less-than-or-equal-to m,n less-than-or-equal-to 7. Taking advantage of an appropriate choice of the total SL thickness D less-than-or-equal-to 0.3-mu-m, we measure the frequencies of AlAs-like TO1 confined phonons from the peak of the reststrahlen band. The GaAs-like TO1 frequencies are obtained by fitting reflectivity spectra to the SL dielectric-response-theory model. Microscopic calculations of confined TO frequencies are performed within an ab initio scheme and successfully compared with the experimental data.
Titolo: | INFRARED REFLECTIVITY BY TRANSVERSE-OPTICAL PHONONS IN (GAAS)M/(ALAS)N ULTRATHIN-LAYER SUPERLATTICES |
Autori: | |
Data di pubblicazione: | 1991 |
Rivista: | |
Abstract: | We report far-infrared reflectivity measurements on (GaAs)m/(AlAs)n superlattices (SL's) with systematically varied layer thicknesses in the range 1 less-than-or-equal-to m,n less-than-or-equal-to 7. Taking advantage of an appropriate choice of the total SL thickness D less-than-or-equal-to 0.3-mu-m, we measure the frequencies of AlAs-like TO1 confined phonons from the peak of the reststrahlen band. The GaAs-like TO1 frequencies are obtained by fitting reflectivity spectra to the SL dielectric-response-theory model. Microscopic calculations of confined TO frequencies are performed within an ab initio scheme and successfully compared with the experimental data. |
Handle: | http://hdl.handle.net/11390/667082 |
Appare nelle tipologie: | 1.1 Articolo in rivista |