Search

Two-dimensional (2D) metallic transition metal dichalcogenides (TMDs) exhibit fascinating quantum effects, such as charge-density-wave (CDW) and weak antilocalization (WAL) effect. Herein, low temperature synthesis of 1T phase VSe

To widen the detection wavelength range and improve the detection sensitivity of SiC-based optoelectronic devices, the SiC/Ge/graphene heterojunction was fabricated by using wet transfer of the graphene following chemical vapor deposition. The Ge films on 4H-SiC(0001) have polycrystalline structure with nano-wire (NWs) and submicron spherical island (SIs) features. Due to the distinct light trapping effect of the Ge NWs, the SiC/GeNWs/graphene heterojunction has an absorbance of more than 90% in the 500-1600 nm range, which is higher than the SiC/GeSIs/graphene heterojunction. And the SiC/GeNWs/graphene heterojunction photodetector exhibits rectification ratio up to 25 at ±2 V and stable photoresponse to the NIR light at zero voltage bias.

Two-dimensional (2D) metallic transition metal dichalcogenides (TMDs) exhibit fascinating quantum effects, such as charge-density-wave (CDW) and weak antilocalization (WAL) effect. Herein, low temperature synthesis of 1T phase VSe2 single crystals with thickness ranging from 3 to 41 nm by chemical vapor deposition (CVD) is reported. The VSe2 shows a decreasing phase transition temperature of the CDW when the thickness is decreased. Moreover, low-temperature magnetotransport measurements demonstrate a linear positive and non-saturating magnetoresistance (MR) of 35% from a 35 nm thick VSe2 at 15 T and 2 K due to CDW induce mobility fluctuations. Surprisingly, Kohler's rule analysis of the MR reveals the non-applicability of Kohler's rule for temperature above 50 K indicating that the MR behavior cannot be described in terms of semiclassical transport on a single Fermi surface with a single scattering time. Furthermore, WAL effect is observed in the 4.2 nm thick VSe2 at low magnetic fields at 2 K, revealing the contribution of the quantum interference effect at the 2D limit. The phase coherence length [Formula: see text] and spin-orbit scattering length [Formula: see text] were determined to be 73 nm and 18 nm at 2 K, respectively. Our work opens new avenues to study the fundamental quantum phenomena in CVD-deposited TMDs.