Angular-dependences of giant in-plane and interlayer magnetoresistances in Bi 2Te 3 bulk single crystals

Angular-dependences of in-plane and interlayer magnetotransport properties in n-type Bi 2Te 3 bulk single crystals have been investigated over a broad range of temperatures and magnetic fields. Giant in-plane magnetoresistances (MR) of up to 500 and interlayer MR of up to 200 were observed, respectively. The observed MR exhibits quadratic field dependences in low fields and linear field dependences in high fields. The angular dependences of the MR represent strong anisotropy and twofold oscillations. The observed angle-dependent, giant MR might result from the strong coulomb scattering of electrons as well as impurity scattering in the bulk conduction bands of n-type Bi 2Te 3. The strong anisotropy of the MR may be attributable to the anisotropy of electron mobility, effective mass, and relaxation time in the Fermi surface. The observed giant anisotropic MR in n-type Bi 2Te 3 bulk single crystals paves the way for Bi 2Te 3 single crystals to be useful for practical applications in magnetoelectronic devices such as disk reading heads, anisotropic magnetic sensors, and other multifunctional electromagnetic applications