TY - JOUR
T1 - Core excitons and conduction-band structures in orthorhombic GeS, GeSe, SnS, and SnSe single crystals
AU - Taniguchi, M.
AU - Johnson, R. L.
AU - Ghijsen, J.
AU - Cardona, M.
PY - 1990/12/1
Y1 - 1990/12/1
N2 - Photoelectron partial-yield and constant-initial-state (CIS) spectra of the layered-semiconductor GeS, GeSe, SnS0.9Se0.1, and SnSe single crystals were investigated with use of synchrotron radiation. The cation d core (Ge 3d and Sn 4d) yield spectra show intense and sharp doublets due to cation-derived core excitons. The CIS spectra exhibit strong resonance due to an interference between the direct-recombination process of the core excitons and the direct-excitation process of the valence electrons. The strong resonance is characteristic of core excitons with a long lifetime and a fairly localized nature. The anion p and d core (S 2p and Se 3d) yield spectra are much broader than the cation d core spectra and reflect the density of states (DOS) of the conduction bands. Energies of the experimental DOS peaks compare favorably with conduction-band features derived from interband optical-absorption spectra.
AB - Photoelectron partial-yield and constant-initial-state (CIS) spectra of the layered-semiconductor GeS, GeSe, SnS0.9Se0.1, and SnSe single crystals were investigated with use of synchrotron radiation. The cation d core (Ge 3d and Sn 4d) yield spectra show intense and sharp doublets due to cation-derived core excitons. The CIS spectra exhibit strong resonance due to an interference between the direct-recombination process of the core excitons and the direct-excitation process of the valence electrons. The strong resonance is characteristic of core excitons with a long lifetime and a fairly localized nature. The anion p and d core (S 2p and Se 3d) yield spectra are much broader than the cation d core spectra and reflect the density of states (DOS) of the conduction bands. Energies of the experimental DOS peaks compare favorably with conduction-band features derived from interband optical-absorption spectra.
UR - http://www.scopus.com/inward/record.url?scp=0008934767&partnerID=8YFLogxK
U2 - 10.1103/PhysRevB.42.3634
DO - 10.1103/PhysRevB.42.3634
M3 - Article
AN - SCOPUS:0008934767
SN - 0163-1829
VL - 42
SP - 3634
EP - 3643
JO - Physical review. B, Condensed matter
JF - Physical review. B, Condensed matter
IS - 6
ER -