Akademik Məlumat İdarəetmə Sistemi
Japanese Journal of Applied Physics, vol.50, no.5 PART 3, 2011 (SCI-Expanded, Scopus)
Electronic energy bands of the Tl-based ternary chalcogenide TlGaTe 2 with a quasi one-dimensional crystalline structure have been studied by means of high resolution angle-resolved photoemission spectroscopy (ARPES) in order to check for dispersive structures similar to the Dirac cone observed in the surface bands of Bi-based binary chalcogenides. Two linear dispersive structures which are not reproduced in band calculations for bulk material have been observed in the energy band along the Γ-N direction perpendicular to the chains. These dispersions form a cross-type structure that is centered at the Γ point and extends along the Γ-H-T direction parallel to the chains, reflecting, in our opinion, one-dimensional features of surface morphology of TlGaTe2. The cross-type structure, the energy position of which linearly varies with excitation photon energy, is observed only for high-grade quality surfaces of TlGaTe2. It is therefore assumed that the observed peculiar dispersive structure is caused by the Dirac-type dispersion of high-lying surface conduction bands and that ARPES detects the joint density of states. © 2011 The Japan Society of Applied Physics.