TY - JOUR
AU - Staunton, J. B.
AU - Banerjee, R.
AU - dos Santos Dias, Manuel
AU - Deak, A.
AU - Szunyogh, L.
TI - Fluctuating local moments, itinerant electrons, and the magnetocaloric effect: Compositional hypersensitivity of FeRh
JO - Physical review / B
VL - 89
IS - 5
SN - 1098-0121
CY - College Park, Md.
PB - APS
M1 - FZJ-2014-03350
SP - 054427
PY - 2014
AB - We describe an ab initio disordered local moment theory for materials with quenched static compositional disorder traversing first-order magnetic phase transitions. It accounts quantitatively for metamagnetic changes and the magnetocaloric effect. For perfect stoichiometric B2-ordered FeRh, we calculate the transition temperature of the ferromagnetic-antiferromagnetic transition to be Tt= 495 K and a maximum isothermal entropy change in 2 T of |ΔS|=21.1 J K−1 kg−1. A large (40%) component of |ΔS| is electronic. The transition results from a fine balance of competing electronic effects which is disturbed by small compositional changes; e.g., swapping just 2% Fe of “defects” onto the Rh sublattice makes Tt drop by 290 K. This hypersensitivity explains the narrow compositional range of the transition and impurity doping effects.
LB - PUB:(DE-HGF)16
UR - <Go to ISI:>//WOS:000332409800002
DO - DOI:10.1103/PhysRevB.89.054427
UR - https://juser.fz-juelich.de/record/153871
ER -