Single Crystal Growth of the CeCu2Si2 Intermetallic Compound by a Vertical Floating Zone Method

Large CeCu2Si2 single crystals were grown by a vertical floating zone method with optical heating at slow zone traveling rates of 1−3 mm/h. Elevated Ar pressure of 3 MPa in the growth chamber was applied and floating zone was controlled by an in situ temperature measurement in order to minimize Cu evaporation. The compound exhibits incongruent melting behavior with Ce2CuSi3 primary phase precipitates in the initial growth phase. Gradual accumulation of Cu in the floating zone finally led to the TSFZ growth mode of CeCu2Si2 single crystals homogeneous over the whole cross section. The obtained CeCu2Si2 crystal was proven to be single phase with no sign of Cu depletion in the final part, the X-ray single crystal diffraction study proved its excellent quality. It exhibited the S-type behavior with heavy fermion superconducting properties at T Tc = 0.58 K.