title: Low temperature magnetothermoelectric effect and magnetoresistance in Te vapor annealed Bi2Te3.
abstract: The electrical properties of single crystals of p-type Bi(2)Te(3) are shown to be tuned by annealing as-grown crystals in elemental Te vapor at temperatures in the range of 400-420 °C. While as-grown nominally stoichiometric Bi(2)Te(3) has p-type conductivity below room temperature, Te vapor annealed Bi(2)Te(3) shows a cross over from p- to n-type behavior. The temperature dependent resistivity of the Te annealed crystals shows a characteristic broad peak near 100 K. Applied magnetic fields give rise to a large low temperature magnetothermoelectric effect in the Te annealed samples and enhance the low temperature peak in the resistivity. Further, Te annealed Bi(2)Te(3) shows a large positive magnetoresistance, ∼ 200% at 2 K, and ∼ 15% at room temperature. The annealing procedure described can be employed to optimize the properties of Bi(2)Te(3) for study as a topological insulator.
authors.affiliation: Department of Chemistry, Princeton University, Princeton, NJ 08544, USA.
authors.forename: Y S
authors.initials: YS
authors.lastname: Hor
authors.forename: D
authors.initials: D
authors.lastname: Qu
authors.forename: N P
authors.initials: NP
authors.lastname: Ong
authors.forename: R J
authors.initials: RJ
authors.lastname: Cava
mesh_terms: D001729:Bismuth / Q000737:chemistry*; D003460:Crystallization / Q000379:methods*; D005740:Gases / Q000737:chemistry*; D008280:Magnetics; D012666:Semiconductors; D013691:Tellurium / Q000737:chemistry*; D013696:Temperature
chemical_list: D005740:Gases; D013691:Tellurium; D001729:Bismuth