Unconventional spin relaxation involving localized vibrational modes in Ho single-atom magnets

0533910 - FZÚ 2021 RIV US eng J - Journal Article
Donati, F. - Rusponi, S. - Stepanow, S. - Persichetti, L. - Singha, A. - Juraschek, D.M. - Wäckerlin, Christian - Baltic, R. - Pivetta, M. - Diller, K. - Nistor, C. - Dreiser, J. - Kummer, K. - Velez-Fort, E. - Spaldin, N.A. - Brune, H. - Gambardella, P.
Unconventional spin relaxation involving localized vibrational modes in Ho single-atom magnets.
Physical Review Letters. Roč. 124, č. 7 (2020), s. 1-6, č. článku 077204. ISSN 0031-9007. E-ISSN 1079-7114
Institutional support: RVO:68378271
Keywords : magnetism * single atom * XMCD * DFT
OECD category: Condensed matter physics (including formerly solid state physics, supercond.)
Impact factor: 9.161, year: 2020
Method of publishing: Limited access
https://doi.org/10.1103/PhysRevLett.124.077204

We investigate the spin relaxation of Ho single atom magnets on MgO=Agð100Þ as a function of temperature and magnetic field. We find that the spin relaxation is thermally activated at low field, while it remains larger than 1000 s up to 30 K and 8 T. This behavior contrasts with that of single molecule magnets and bulk paramagnetic impurities, which relax faster at high field.Combining our results with density functional theory, we rationalize this unconventional behavior by showing that local vibrations activate a two phonon Raman process with a relaxation rate that peaks near zero field and is suppressed at high field. Our work shows the importance of these excitations in the relaxation of axially coordinated magnetic atoms.
Permanent Link: http://hdl.handle.net/11104/0312138