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arXiv · 2502.02005

Conductivity of high-mobility epitaxial GdN

Edward X. M. Trewick·B. J. Ruck·W. F. Holmes-Hewett·H. J. Trodahl
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Abstract

We report electron transport studies of a (001) GdN film grown on the square net presented by the (001) surface of LaAlO3, motivated by recent advances in epitaxial thin-film growth of several lanthanide nitrides. The film we have grown for the purpose is characterised by in-situ RHEED and ex-situ XRD and XRR to show the best crystallinity and smoothest surfaces we have accomplished to date. It shows a clear ferromagnetic transition at $\sim70$ K with a saturation magnetisation within uncertainly of 7 $\mu$B/Gd$^{3+}$ ion, a remanence of 5 $\mu$B/Gd$^{3+}$ ion and a coercive field of $\sim$5 mT. It is doped by $\sim1$% nitrogen vacancies that introduce $\sim3\times10^{20}$ cm$^{-3}$ electrons into the conduction band. The resistivity shows transport in a conduction band doped to degeneracy by $\sim0.01$ electrons/formula unit with a residual resistance ratio of 2 and a Hall resistivity permitting easily-separated ordinary and anomalous Hall components. The mobility is an order of magnitude larger than we have found in earlier films.

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Edward X. M. Trewick, B. J. Ruck, W. F. Holmes-Hewett, H. J. Trodahl. 2025-02-04. Conductivity of high-mobility epitaxial GdN. https://arxiv.org/abs/2502.02005

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