Nuclear resonant time spectra for 119Sn in Co2TiSn Heusler alloy films

Abstract Co 2 TiSn Heusler alloy films were grown on MgO substrates at the substrate temperature between 200 and 600 °C using atomically controlled alternate deposition and magnetic hyperfine field at the Sn nuclei was measured by the Mossbauer spectroscopy and the nuclear resonant scattering method. The relation between the hyperfine field and the structural disorder estimated by X-ray diffraction measurements was also examined. The results showed that the sample prepared at higher substrate temperature has higher degree of L2 1 order and larger hyperfine field. For the Co 2 TiSn film grown at 600 °C, the hyperfine field estimated from the oscillatory pattern of the nuclear resonant time spectra was 6.1 T at room temperature and increased with a decrease of temperature to 7.5, 8.1, and 8.3 T at 200, 100, and 5 K, respectively, which shows that the film prepared by this method and condition has almost the same magnetization value and Curie temperature as bulk samples.