We have synthesized Fe1+yTe thin films by means of molecular beam epitaxy (MBE) under Te-limited growth conditions. We found that epitaxial layer-by-layer growth is possible for a wide range of excess Fe values, wider than expected from what is known on the bulk material. Using x-ray magnetic circular dichroism spectroscopy at the Fe L2,3 and Te M4,5 edges, we observed that films with high excess Fe contain ferromagnetic clusters while films with lower excess Fe remain nonmagnetic. Moreover, x-ray absorption spectroscopy showed that it is possible to obtain films with very similar electronic structure as that of a high quality bulk single crystal Fe1.14Te. Our results suggest that MBE with Te-limited growth may provide an opportunity to synthesize FeTe films with smaller amounts of excess Fe as to come closer to a possible superconducting phase.
@article{arxiv.2002.09507,
title = {Molecular beam epitaxy preparation and in situ characterization of FeTe thin films},
author = {V. M. Pereira and C. N. Wu and C. E. Liu and S. -S. Liao and C. F. Chang and C. -Y. Kuo and C. Koz and U. Schwarz and H. -J. Lin and C. T. Chen. L. H. Tjeng and S. G. Altendorf},
journal= {arXiv preprint arXiv:2002.09507},
year = {2020}
}
Comments
6 pages, 6 figures accepted for publication in Physical Review Materials