材料期刊网

Large, high quality single crystals of Dy2Ti2O7 have been successfully grown by the floating zone technique in an infrared image furnace. The obtained single crystal has been characterized by X-ray diffraction at room temperature and is shown to have the face centred cubic structure, Fd (3) over barm, with a room temperature lattice parameter a = 1.0112(2) nm. The full-width at half-maximum of rocking curves of [111] and [400] Bragg peaks are 0.07 degrees and 0.05 degrees, respectively. Magnetic susceptibility measurements give a Van Vleck paramagnetic parameter of 2.46 x 10(-5) m(3)/mol, the effective moment mu(eff) = 10.24(4)mu(B) and Cure-Weiss temperature Theta(CW) = 1.1 K, indicating weak ferromagnetism for the Dy2Ti2O7 single crystal. The comparative studies of the experiment and theoretical analysis reveal that the long-ranged dipole-dipole interactions dominate the magnetic behaviors of this kind of spin ice system, and the dipolar energy scale D-nm = 3.00 K.