Chemical vapor deposition and temperature-dependent Raman characterization of two-dimensional vanadium ditelluride

Abstract

Two-dimensional vanadium ditelluride has been synthesized on mica, sapphire, and h-BN substrates by atmospheric pressure chemical vapor deposition.

Thickness-Dependent Sign Change of the Magnetoresistance in VTe2 Thin Films

“…Bulk VTe 2 presents a monoclinic distorted 1T' phase below 207 • C [24,25] but recently it has been shown that an undistorted hexagonal 1T structure appears upon a reduction of the thickness [18]. Lattice distortions related to thickness, temperature, and electrical field have led to quantum phases such as charge density waves (CDWs) phases [26,27].…”

“…The 1T structure is composed of one layer of hexagonally arranged vanadium atoms sandwiched between two layers of tellurium atoms in an octahedral configuration, stacked together by weak van der Waals forces (Figure 1a). In a trigonal layered structure, 1T-VTe 2 crystallizes in the space group P-3m1 with hexagonal lattice parameters of a = b = 3.64 Å and c = 6.51 Å [24,28,29].…”

“…Both spectra are composed of one chemical state, without metallic or oxidized bonding. The binding energies of the distinct V-2p and Te-3d doublet peaks indicate that the VTe 2 film consists of the 1T-VTe 2 phase [24,25]. The stoichiometry of the grown film was calculated by fitting the XPS peaks, for which we performed a Shirley background subtraction from the data.…”