TY  - JOUR
AU  - Wagner, Julia
AU  - Häußler, Wolfgang
AU  - Holderer, Olaf
AU  - Bauer, Andreas
AU  - Shapiro, Stephen
AU  - Böni, Peter
TI  - Influence of Concentration Fluctuations on Relaxation Processes in Spin Glasses
JO  - Quantum beam science
VL  - 2
IS  - 4
SN  - 2412-382X
CY  - Barcelona
PB  - MDPI
M1  - FZJ-2018-06880
SP  - 26 -
PY  - 2018
AB  - Using the unique combination of atomically resolved atom probe tomography (APT) and volume averaged neutron (resonance) spin echo (NRSE and NSE) experiments, the influence of nano-scaled clusters on the spin relaxation in spin glasses was studied. For this purpose, the phase transition from the paramagnetic phase to the spin glass phase in an Fe-Cr spin glass with a composition of Fe 17.8 Cr 82.2 was studied in detail by means of NRSE. The microstructure was characterised by APT measurements, which show local concentration fluctuations of Fe and Cr on a length scale of 2 to 5 nm, which lead (i) to the coexistence of ferro- and anti-ferromagnetic clusters and (ii) a change of the magnetic properties of the whole sample, even in the spin glass phase, where spins are supposed to be randomly frozen. We show that a generalized spin glass relaxation function, which was successfully used to describe the phase transition in diluted spin glasses, can also be used for fitting the spin dynamics in spin glasses with significant concentration fluctuations.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000533300900006
DO  - DOI:10.3390/qubs2040026
UR  - https://juser.fz-juelich.de/record/857926
ER  -