Influence of finite-size effects on the Curie temperature of L10-FePt

TY - JOUR

T1 - Influence of finite-size effects on the Curie temperature of L10-FePt

AU - Binh, Nguyen Thanh

AU - Ruta, Sergiu

AU - Hovorka, Ondrej

AU - Evans, Richard F.L.

AU - Chantrell, Roy W.

N1 - ©2022 American Physical Society. Uploaded in accordance with the publisher’s self-archiving policy. Further copying may not be permitted; contact the publisher for details

PY - 2022/8/17

Y1 - 2022/8/17

N2 - We employ an atomistic model using a nearest-neighbor Heisenberg Hamiltonian exchange to study computationally the dependence of the Curie temperature of L10-FePt on finite-size and surface effects in heat-assisted magnetic recording (HAMR) media. We demonstrate the existence of a size threshold at 3.5 nm below which the impact of finite-size effects starts to permeate into the center of the grains and contributes to the reduction of the Curie temperature. We find a correlation between the Curie temperature and the percentage of atomistic bonds lost on the surface as a function of grain size, which can be extended to apply to not only L10-FePt but also generic magnetic systems of any crystal structure. In a recording medium, the inevitable grain size dispersion leads to an irreducible contribution to the dispersion of the Curie temperature. Therefore, our paper gives insight into finite-size effects, which have been predicted to be a serious limitation of HAMR.

AB - We employ an atomistic model using a nearest-neighbor Heisenberg Hamiltonian exchange to study computationally the dependence of the Curie temperature of L10-FePt on finite-size and surface effects in heat-assisted magnetic recording (HAMR) media. We demonstrate the existence of a size threshold at 3.5 nm below which the impact of finite-size effects starts to permeate into the center of the grains and contributes to the reduction of the Curie temperature. We find a correlation between the Curie temperature and the percentage of atomistic bonds lost on the surface as a function of grain size, which can be extended to apply to not only L10-FePt but also generic magnetic systems of any crystal structure. In a recording medium, the inevitable grain size dispersion leads to an irreducible contribution to the dispersion of the Curie temperature. Therefore, our paper gives insight into finite-size effects, which have been predicted to be a serious limitation of HAMR.

UR - http://www.scopus.com/inward/record.url?scp=85137678187&partnerID=8YFLogxK

U2 - 10.1103/PhysRevB.106.054421

DO - 10.1103/PhysRevB.106.054421

M3 - Article

AN - SCOPUS:85137678187

SN - 2469-9950

VL - 106

JO - Physical Review B

JF - Physical Review B

IS - 5

M1 - 054421

ER -