Thickness-dependent conductance in Sb2SeTe2 topological insulator nanosheets

Abstract

The conductivity increases as thickness decreases in a series of Sb2SeTe2 topological insulator nanosheets with thickness ranging from 80 to 200 nm, where the sheet conductance is proportional to the thickness. The corresponding sheet conductance of the surface state is 8.7 e2/h which is consistent with the values extracted from the temperature dependent Shubnikov-de Haas oscillations at high magnetic fields. The extracted Fermi momentum is the same as the results from the ARPES value, and the Berry phase is π. These support that the thickness dependent sheet conductance originates from the combination of the surface state and the bulk state.

The thickness-induced magneto-transport and optic properties enhancement in Sb2Te3 flakes

“…The resultant material was then used as a feeding rod for the RHFZ experiment. Our previous work demonstrated that TI with extremely high uniformity can be obtained using the RHFZ method 8 , 9 , 21 – 23 . After growth, the crystals were furnace cooled to room temperature.…”

Highly responsive photoconductance in a Sb2SeTe2 topological insulator nanosheet at room temperature

“…Several experimental works were performed on different topological insulators, which exhibited various kinds of characteristics that are expected to be able to be used in a wide range of applications. [10][11][12][13][14][15][16][17][18] It has come to our attention that most photocurrent experiments have mainly focused on the application of visible and near infrared light to topological insulators, graphene-topological insulator heterostructures and 2D TMDs. Work with ultraviolet light is relatively rare, and the reported photocurrent performance is low.…”

The Extremely Enhanced Photocurrent Response in Topological Insulator Nanosheets with High Conductance

“…1 , the linear voltage-current relation supports that nanosheets reveal a metallic behavior. The light-induced electron-hole pairs would travel to two electrode contacts due to the applied voltage bias [ 27 – 29 ]. Following Ohm’s law, the related photocurrent could be determined through the relation I ph = V G where V is the applied voltage bias between two electrodes.…”