The anisotropic band structure of layered In4Se3(001)

Abstract

Losovyj, Yaroslav B.; Makinistian, L.; Albanesi, E. A.; Pethukov, A. G.; Liu, Jing; Galiy, P.; Dveriy, O. R.; and Dowben, Peter A., "The anisotropic band structure of layered In 4 Se 3 (001)" (2008 There is discernable and significant band dispersion along both high symmetry directions for cleaved ordered surfaces of the layered In 4 Se 3 ͑001͒. The extent of dispersion of approximately 1 eV is observed along the surface chain rows, and about 0.5 eV perpendicular to the surface "furrows," consistent with theoretical expectations. A possible surface state exists at the surface Brillouin zone edge, in the direction perpendicular to the chains, in a gap of the projected bulk band structure. Excluding the possible surface state, the experimental hole mass is 5.5 times greater along the chains than perpendicular to the chains, but the dispersion is easier to discern.

Tunable two-dimensional electron gas at the surface of thermoelectric materialIn4Se3

“…Similarly for In 4 Se 3 , as the formal valence of Se is -2 (Ref. 36), the extraction of Se is expected to leave a positively charged vacancy resulting in the downward band-bending. Another possibility can be inferred from the crystal structure of In 4 Se 3 , in which two In atoms per unit cell are naturally intercalated (or "sandwiched") within the Van der Waals gap between the atomic layers.…”

Chemical Potential Tuning and Enhancement of Thermoelectric Properties in Indium Selenides

“…It was confirmed that the electronic band structure of In 4 Se 3 is very anisotropic. The effective mass of hole along the chain direction is 5.5 times greater than the direction perpendicular to the chains, implying anisotropic band dispersion between electron and hole bands [19]. In spite of the low dimensional crystal structure and anisotropic electronic structure of In 4 Se 3 , it is known that the charge density wave is unlikely in this material [20].…”

Thermoelectric properties of Se-deficient and Pb-/Sn-codoped In4Pb0.01Sn0.03Se3− polycrystalline compounds

“…The specific heat Cp was measured by physical property measurement system (PPMS, Quantum Design, USA). [10,16]. If the vacancy in the Se3-site is employed, the charge re-distribution can relax the cluster.…”