| Autor: |
Helmut Fritzsche, G. J. Nieuwenhuys, M. Saoudi, M. B. S. Hesselberth |
| Rok vydání: |
2007 |
| Předmět: |
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| Zdroj: |
Physical review letters. 100(5) |
| ISSN: |
0031-9007 |
| Popis: |
We used polarized neutron reflectometry to determine the temperature dependence of the magnetization of thin AuFe films with 3% Fe concentration. We performed the measurements in a large magnetic field of 6 T in a temperature range from 295 to 2 K. For the films in the thickness range from 500 to 20 nm we observed a Brillouin-type behavior from 295 K down to 50 K and a constant magnetization of about $0.9{\ensuremath{\mu}}_{B}$ per Fe atom below 30 K. However, for the 10 nm thick film we observed a Brillouin-type behavior down to 20 K and a constant magnetization of about $1.3{\ensuremath{\mu}}_{B}$ per Fe atom below 20 K. These experiments are the first to show a finite-size effect in the magnetization of single spin-glass films in large magnetic fields. Furthermore, the ability to measure the deviation from the paramagnetic behavior enables us to prove the existence of the spin-glass state where other methods relying on a cusp-type behavior fail. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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