Plasma Edge in Bi2Te3

Abstract

The reflectance minima associated with the free carrier plasma edges in pand n-type Bi 2 Te3 have been observed at 78° and 300 o K. The data together with the measured Hall and Seebeck coefficients have yielded combined band structure-relaxation time parameters when proper account is taken of the anisotropy. These are compared with the results of other experiments from which similar information has been obtained. For n-type Bi2Tea fair agreement is found with galvanomagnetic and optical band structure determinations. For p-type material the agreement with the results of similar experiments is considerably poorer but recent de Haas-van Alphen and galvanomagnetic measurements have established the value of the parameter measured in this experiment to within approximately the experimental error.

Anomalous temperature dependence of the effective mass in p -type Bi2Te3

“…Bismuth telluride (Bi 2 Te 3 ) is a layered narrow-gap semiconductor that has been extensively studied as an excellent thermoelectric material for energy conversion (Seebeck effect) and cooling applications (Peltier effect) [1][2][3]. Its bulk gap is sufficiently large to predestinate it as a possible candidate for spintronics applications [4].…”

“…Its crystal structure is made of three van der Waals coupled quintuple layers stacked along the trigonal c axis. The layers are formed by five covalently bonded atomic layers alternating as Te(1)-Bi-Te(2)-Bi-Te (1). Because of this structure the material is strongly anisotropic and can be easily cleaved along the planes perpendicular to the trigonal c axis.…”