Presentation Information
[10a-C310-4]Growth of Complex Nitride NdTaN2 and GdTaN2 Thin Films by Molecular Beam Epitaxy
〇Kosuke Takiguchi1, Spencer Hryciw1, Yoshiharu Krockenberger1, Kunihashi Yoji1, Hideki Yamamoto1 (1.NTT BRL)
Keywords:
complex nitride,molecular beam epitaxy,new material
Novel ternary complex nitrides, NdTaN2 and GdTaN2, were synthesized as epitaxial thin films using molecular beam epitaxy (MBE). The fluxes of Nd, Gd, and Ta were precisely controlled by electron-beam evaporation and real-time emission spectroscopy, while nitrogen radicals were used for nitridation. X-ray diffraction measurements revealed that both compounds adopt the same crystal structure as the previously reported PrTaN2 phase. Systematic lattice contraction was observed with decreasing lanthanide ionic radius, yielding c-axis lengths of 3.99 Å for NdTaN2 and 3.93 Å for GdTaN2, compared with 4.02 Å for PrTaN2. Electrical transport measurements showed metallic behavior for NdTaN2 and GdTaN2, whereas PrTaN2 is insulating. GdTaN2 exhibited the lowest room-temperature resistivity (4.7 mΩ·cm) and showed magnetic characteristics below 300 K indicative of ferromagnetic or ferrimagnetic ordering.