Low Temperature Magnetothermoelectric Effect and Magnetoresistance in Te Vapor Annealed Bi2Te3
The electrical properties of single crystals of p-type Bi2Te3 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 Bi2Te3 has p-type conductivity below room temperature, Te vapor annealed Bi2Te3 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 Bi2Te3 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 Bi2Te3 for study as a topological insulator.
Y. S. Hor et al., "Low Temperature Magnetothermoelectric Effect and Magnetoresistance in Te Vapor Annealed Bi2Te3," Journal of Physics Condensed Matter, vol. 22, no. 37, IOP Publishing, Aug 2010.
The definitive version is available at http://dx.doi.org/10.1088/0953-8984/22/37/375801
Keywords and Phrases
Annealed Samples; Annealing Procedures; Applied Magnetic Fields; As-grown; As-grown Crystal; Cross Over; Electrical Property; Low Temperatures; Magnetothermoelectric; P-type; P-type Conductivity; Positive Magnetoresistance; Room Temperature; Te Vapor; Temperature-dependent Resistivity; Electric Resistance; Magnetic Field Effects; Single Crystals; Tellurium Compounds
International Standard Serial Number (ISSN)
Article - Journal
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