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arXiv · 0912.0560

"Graphene-Like" Exfoliation of Atomically-Thin Bismuth Telluride Films

Desalegne Teweldebrhan·Vivek Goyal·Muhammad Rahman·Alexander A. Balandin
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Abstract

We report on graphene-like exfoliation of the large-area crystalline films and ribbons of bismuth telluride with the thicknesses of a few atoms. It is demonstrated that bismuth telluride, the most important material for thermoelectric industry, can be mechanically separated into its building blocks -[Te-Bi-Te-Bi-Te]- atomic five-folds with the thickness of ~1 nm and even further - to subunits with smaller thicknesses. The atomically-thin crystals can be structured into suspended crystalline ribbons providing quantum confinement in two dimensions. The quasi two-dimensional (2-D) crystals of bismuth telluride revealed high electrical conductivity. The proposed atomic-layer engineering of bismuth telluride opens up a principally new route for drastic enhancement of the thermoelectric figure of merit.

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Desalegne Teweldebrhan, Vivek Goyal, Muhammad Rahman, Alexander A. Balandin. 2009-12-03. "Graphene-Like" Exfoliation of Atomically-Thin Bismuth Telluride Films. https://arxiv.org/abs/0912.0560

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