Role of disorder in magnetic and conducting properties of U–Mo and U–Mo–H thin films

Abstract Crystal structure, magnetic and electrical properties of thin U-Mo films and their hydrides prepared by reactive sputter deposition from metallic targets is studied. The films are metallic but with high values of electrical resistivity. Both bcc U0.79Mo0.21 thin film and the hydride (UH3)0.74Mo0.26 (β-UH3 structure type) have a very strong texture. Superconductivity was identified below Tc = 0.55 K for U0.79Mo0.21. The critical field of 1.0 T is exceeding that of α-U (0.3 T). The hydride film (UH3)0.74Mo0.26 is a ferromagnet with the Curie temperature TC = 165 K, higher concentration of Mo somewhat reduces the TC value. The U-Mo films and hydrides exhibit the net negative temperature coefficient of resistivity, TCR = dρ/dT, attributed to the randomness on atomic scale, yielding very strong scattering of electrons and weak localization.