Growth and Characterization of Sb 2 Se 3 Single Crystals for Fundamental Studies

Three methods of growing bulk crystalline samples of $Sb_{2} Se_{3}$ to provide material for basic studies have been investigated and preliminary characterization is reported. These growth methods were: a) melt-growth, similar to vertical Bridgman, b) dynamic vapor transport over a temperature gradient (Piper-Polich method) and c) a static vapor method in which the source material is transported in nearly iso-thermal conditions. The melt-growth method produced the largest single crystals (up to 4 mm diameter), while the vapor methods both yielded polycrystalline boules with mm-sized grains. Powder XRD confirmed the boules to comprise orthorhombic $Sb_{2} Se_{3}$, having lattice parameters a = 11.7808 A b = 3.9767 A and c = 11.6311 A. Cleavage facets were parallel to (100). Raman peaks at 191 (A g and 211 cm -1 were excited anisotropically. FTIR reflectance features showed some sensitivity to s- and ppolarization.