TY - JOUR
T1 - Magneto-optic response of the metallic antiferromagnet Fe2As to ultrafast temperature excursions
AU - Yang, Kexin
AU - Kang, Kisung
AU - Diao, Zhu
AU - Ramanathan, Arun
AU - Karigerasi, Manohar H.
AU - Shoemaker, Daniel P.
AU - Schleife, André
AU - Cahill, David G.
N1 - Funding Information:
This work was undertaken as part of the Illinois Materials Research Science and Engineering Center, supported by the National Science Foundation MRSEC program under NSF Award No. DMR-1720633. This work made use of the Illinois Campus Cluster, a computing resource that is operated by the Illinois Campus Cluster Program (ICCP) in conjunction with the National Center for Supercomputing Applications (NCSA) and which is supported by funds from the University of Illinois at Urbana-Champaign. This research is part of the Blue Waters sustained-petascale computing project, which is supported by the National Science Foundation (Awards No. OCI-0725070 and No. ACI-1238993) and the state of Illinois. Blue Waters is a joint effort of the University of Illinois at Urbana-Champaign and its National Center for Supercomputing Applications. This research used resources of the Spallation Neutron Source, a DOE Office of Science User Facility operated by Oak Ridge National Laboratory, and the Advanced Photon Source, a DOE Office of Science User Facility operated for the DOE Office of Science by Argonne National Laboratory under Contract No. DE-AC02-06CH11357. Z.D. acknowledges support from the Swedish Research Council (VR) under Grant No. 2015-00585, cofunded by Marie Skłodowska-Curie Actions (Project INCA 600398).
Publisher Copyright:
© 2019 American Physical Society.
PY - 2019/12/23
Y1 - 2019/12/23
N2 - The linear magneto-optic Kerr effect (MOKE) is often used to probe magnetism of ferromagnetic materials, but MOKE cannot be applied to collinear antiferromagnets due to the cancellation of sublattice magnetization. Magneto-optic constants that are quadratic in magnetization, however, provide an approach for studying antiferromagnets on picosecond timescales. Here, we combine transient measurements of linear birefringence and optical reflectivity to study the optical response of Fe2As to small ultrafast temperature excursions. We performed temperature-dependent pump-probe measurements on crystallographically isotropic (001) and anisotropic (010) faces of Fe2As bulk crystals. We find that the largest optical signals arise from changes in the index of refraction along the z axis, perpendicular to the Néel vector. Both real and imaginary parts of the transient optical birefringence signal approximately follow the temperature dependence of the magnetic heat capacity, as expected if the changes in dielectric function are dominated by contributions of exchange interactions to the dielectric function.
AB - The linear magneto-optic Kerr effect (MOKE) is often used to probe magnetism of ferromagnetic materials, but MOKE cannot be applied to collinear antiferromagnets due to the cancellation of sublattice magnetization. Magneto-optic constants that are quadratic in magnetization, however, provide an approach for studying antiferromagnets on picosecond timescales. Here, we combine transient measurements of linear birefringence and optical reflectivity to study the optical response of Fe2As to small ultrafast temperature excursions. We performed temperature-dependent pump-probe measurements on crystallographically isotropic (001) and anisotropic (010) faces of Fe2As bulk crystals. We find that the largest optical signals arise from changes in the index of refraction along the z axis, perpendicular to the Néel vector. Both real and imaginary parts of the transient optical birefringence signal approximately follow the temperature dependence of the magnetic heat capacity, as expected if the changes in dielectric function are dominated by contributions of exchange interactions to the dielectric function.
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U2 - 10.1103/PhysRevMaterials.3.124408
DO - 10.1103/PhysRevMaterials.3.124408
M3 - Article
AN - SCOPUS:85077324661
SN - 2475-9953
VL - 3
JO - Physical Review Materials
JF - Physical Review Materials
IS - 12
M1 - 124408
ER -