We report successful growth of flux free large single crystals of superconducting FeSe 1/2 Te 1/2 with typical dimensions of up to few cm. The AC and DC magnetic measurements revealed the superconducting transition temperature (T c ) value of around 11.5K and the isothermal MH showed typical type-II superconducting behavior. The lower critical field (H c1 ) being estimated by measuring the low field isothermal magnetization in superconducting regime is found to be above 200Oe at 0K. The temperature dependent electrical resistivity ρ(T ) showed the T c (onset) to be 14K and the T c (ρ=0) at 11.5K. The electrical resistivity under various magnetic fields i.e., ρ(T)H for H//ab and H//c demonstrated the difference in the width of T c with applied field of 14Tesla to be nearly 2K, confirming the anisotropic nature of superconductivity. The upper critical and irreversibility fields at absolute zero temperature i.e., H c2 (0) and H irr (0) being determined by the conventional one-band Werthamer-Helfand-Hohenberg (WHH) equation for the criteria of normal state resistivity (ρ n ) falling to 90% (onset), and 10% (offset) is 76.9Tesla, and 37.45Tesla respectively, for H//c and 135.4Tesla, and 71.41Tesla respectively, for H//ab. The coherence length at the zero temperature is estimated to be above 20Ǻ by using the Ginsburg-Landau theory. The activation energy for the FeSe 1/2 Te 1/2 in both directions H//c and H//ab is determined by using Thermally Activation Flux Flow (TAFF) model.

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 Bi 2 Se 3 topological insulator, which is being is grown by self flux method through solid state reaction from high temperature (950˚C) melt and slow cooling (2˚C/hour) of constituent elements. Bi 2 Se 3 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 Bi 2 Se 3 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 (R H ) is seen nearly invariant with negative carrier sign down to 5K albeit having near periodic oscillations above 100K. Heat capacity (C p ) versus temperature plot is seen without any phase transitions down to 5K and is well fitted (Cp = γT + βT 3 ) at low temperature with calculated Debye temperature (Ѳ D ) value of 105.5K. Clear Raman peaks are seen at 72, 131 and 177 cm -1 corresponding to A 1g 1 , E g 2 and A 1g 2 respectively. Though, two distinct asymmetric characteristic peak shapes are seen for Bi 4f 7/2 and Bi 4f 5/2 , 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 Bi 2 Se 3 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 Bi 2 Se 3 crystal are reported here.