Core-excitonic lines at the Al2psurface optical-absorption threshold of AlAs and AlP

Abstract
The optical-absorption spectra of AlAs and AlP exhibit unusual featuresstrong Al 2p core-excitonic lines. The data were obtained with synchrotron-radiation photoemission in the partial-yield mode. The analysis was based on the approach proposed by Johnson, Fock, Ley, and Cardona for AlSb and on Onodera and Toyozawa’s exciton theory.