Atomically resolved magnetic structure of a Gd-Au surface alloy

We gratefully acknowledge financial support from the Office of Naval Research via Grant No. N00014-16-1-2900. Moreover, M.A. and J.B. acknowledge funding from the Spanish MINECO under Contracts No. MAT2013-46593-C6- 4-P and No. MAT2016-78293-C6-5-R as well as the Basque Government Grants No. IT621-13 and No. IT-756-13. T.H. acknowledges support by the DFG under Grant No. HA 6037/2-1. E.S. acknowledges financing from Polish budget funds for science in 2014–2017 as a research project in the program “Diamond Grant” No. 0084/DIA/2014/43. M.H. acknowledges the support from the Ministry of Science and Higher Education in Poland within Project realized at Faculty of Technical Physics, Poznan University of Technology, and Poznan Supercomputing and Networking Center (PSNC)