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The growth and study of materials showing novel topological states of matter

is one of the frontiers in condensed matter physics. Among this class of materials,

the nitride antiperovskite Cu3PdN has been proposed as a new three-dimensional

Dirac semimetal. However, the experimental realization of Cu3PdN and the

consequent study of its electronic properties have been hindered due to the

difficulty of synthesizing this material. In this study, we report fabrication and

both structural and transport characterization of epitaxial Cu3PdN thin films

grown on (001)-oriented SrTiO3 substrates by reactive magnetron sputtering

and post-annealed in NH3 atmosphere. The structural properties of the films,

investigated by x-ray diffraction and scanning transmission electron microscopy,

establish single phase Cu3PdN exhibiting cube-on-cube

epitaxy (001)[100]Cu3PdN||(001)[100]SrTiO3. Electrical transport measurements

of as-grown samples show metallic conduction with a small temperature coefficient

of the resistivity of 1.5 × 10−4 K−1 and a positive Hall coefficient. Post-annealing in

NH3 results in the reduction of the electrical resistivity accompanied by the Hall

coefficient sign reversal. Using a combination of chemical composition analyses and 

ab initio band structure calculations, we discuss the interplay between nitrogen

stoichiometry and magneto-transport results in the framework of the electronic band

structure of Cu3PdN. Our successful growth of thin films of antiperovskite Cu3PdN

opens the path to further investigate its physical properties and their dependence on

dimensionality, strain engineering, and doping.
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