Open Access Te Herenga Waka-Victoria University of Wellington
Browse
Chan_Natali_ASS23.pdf (1.37 MB)

Epitaxial growth of gadolinium and samarium thin films and their subsequent facile nitridation at ambient temperatures

Download (1.37 MB)
journal contribution
posted on 2024-03-27, 02:12 authored by JR Chan, CA Casey-Stevens, M Le Ster, A Shaib, A Tadich, BCC Cowie, Harry TrodahlHarry Trodahl, SA Brown, Simon GranvilleSimon Granville, Benjamin RuckBenjamin Ruck, AL Garden, Franck NataliFranck Natali
Lanthanide nitride species have recently been shown to be easily formed at ambient temperatures and low pressures via the reaction of clean lanthanide surfaces with molecular nitrogen. However, understanding and predicting the nature and efficiency of this process is still in its infancy. In this work we report on the nitridation of the surface of two lanthanide metals, gadolinium (Gd) and samarium (Sm). To that end, epitaxial gadolinium and samarium thin layers are grown on AlN(0001) by molecular beam epitaxy and exposed to molecular nitrogen in high vacuum conditions and ambient temperature. In situ reflection high-energy electron diffraction is used to monitor the growth of Gd in real time, as well as the subsequent exposure to nitrogen, showing a clear transition from a pure Gd surface to a gadolinium nitride (GdN) surface layer. The formation of a nitride layer is further reinforced by magnetic measurements showing clear contributions from the Gd metal and GdN surface layers. Formation of SmN is investigated using synchrotron X-ray photoelectron spectroscopy to probe the surface of Sm pre- and post-nitrogen exposure, showing a change in the surface valence from divalent to trivalent samarium, and confirming the nitridation of the pure Sm surface layer.

Funding

Magnetic Memory for Superconducting and Computing (NSC7a) | Funder: Ministry of Business, Innovation and Employment

History

Preferred citation

Chan, J. R., Casey-Stevens, C. A., Le Ster, M., Shaib, A., Tadich, A., Cowie, B. C. C., Trodahl, H. J., Brown, S. A., Granville, S., Ruck, B. J., Garden, A. L. & Natali, F. (2023). Epitaxial growth of gadolinium and samarium thin films and their subsequent facile nitridation at ambient temperatures. Applied Surface Science, 632, 157550-157550. https://doi.org/10.1016/j.apsusc.2023.157550

Journal title

Applied Surface Science

Volume

632

Publication date

2023-09-30

Pagination

157550-157550

Publisher

Elsevier BV

Publication status

Published

ISSN

0169-4332

eISSN

1873-5584

Article number

157550

Language

en