  We report electrical (angular magneto-resistance, and Hall), thermal (heat
capacity) and spectroscopic (Raman, x-ray photo electron, angle resolved photo
electron) characterization of bulk Bi2Se3 topological insulator, which is being
is grown by self flux method through solid state reaction from high temperature
(950C) melt and slow cooling (2C/hour) of constituent elements. Bi2Se3
exhibited metallic behaviour down to 5K. Magneto transport measurements
revealed linear up to 400% and 30% MR at 5K under 14 Tesla field in
perpendicular and parallel field direction respectively. We noticed that the
magneto-resistance (MR) of Bi2Se3 is very sensitive to the angle of applied
field. MR is maximum when the field is normal to the sample surface, while it
is minimum when the field is parallel. Hall coefficient (RH) is seen nearly
invariant with negative carrier sign down to 5K albeit having near periodic
oscillations above 100K. Heat capacity (Cp) versus temperature plot is seen
without any phase transitions down to 5K and is well fitted (Cp = gammaT +
betaT3) at low temperature with calculated Debye temperature (ThetaD) value of
105.5K. Clear Raman peaks are seen at 72, 131 and 177 cm-1 corresponding to
A1g1, Eg2 and A1g2 respectively. Though, two distinct asymmetric characteristic
peak shapes are seen for Bi 4f7/2 and Bi 4f5/2, the Se 3d region is found to be
broad displaying the overlapping of spin - orbit components of the same.
Angle-resolved photoemission spectroscopy (ARPES) data of Bi2Se3 revealed
distinctly the bulk conduction bands (BCB), surface state (SS), Dirac point
(DP) and bulk valence bands (BVB) and 3D bulk conduction signatures are clearly
seen. Summarily, host of physical properties for as grown Bi2Se3 crystal are
reported here.
