Magnetic Correlations in the Quasi-Two-Dimensional Semiconducting Ferromagnet CrSiTe3

Williams, Travis J.; Aczel, Adam A.; Lumsden, Mark D.; Nagler, Stephen E.; Stone, Matthew B.; Yan, Jiaqiang -Q.; Mandrus, D.

doi:10.1103/PhysRevB.92.144404

Title: Magnetic Correlations in the Quasi-Two-Dimensional Semiconducting Ferromagnet CrSiTe₃

Journal Article · Fri Oct 02 00:00:00 EDT 2015 · Physical Review. B, Condensed Matter and Materials Physics

DOI: https://doi.org/10.1103/PhysRevB.92.144404 · OSTI ID:1222556

Williams, Travis J. ^[1]; Aczel, Adam A. ^[1]; Lumsden, Mark D. ^[1]; Nagler, Stephen E. ^[1]; Stone, Matthew B. ^[1]; Yan, Jiaqiang -Q. ^[2]; Mandrus, D. ^[2]

Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Univ. of Tennessee, Knoxville, TN (United States)

Intrinsic, 2D ferromagnetic semiconductors are an important class of materials for overcoming dilute magnetic semiconductors’ limitations for spintronics. CrSiTe₃ is a particularly interesting material of this class, since it can likely be exfoliated to single layers, for which T_c is predicted to increase dramatically. Establishing the nature of the bulk material’s magnetism is necessary for understanding the thin-film magnetic behavior and the material’s possible applications. In this work, we use elastic and inelastic neutron scattering to measure the magnetic properties of single crystalline CrSiTe₃. We find a very small single ion anisotropy that favors magnetic ordering along the c-axis and that the measured spin waves fit well to a model in which the moments are only weakly coupled along that direction. Then, we find that both static and dynamic correlations persist within the ab-plane up to at least 300 K, which is strong evidence of the material's 2D characteristics that are relevant for future studies on thin film and monolayer samples.

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Research Organization:: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

Sponsoring Organization:: USDOE

Grant/Contract Number:: AC05-00OR22725

OSTI ID:: 1222556

Journal Information:: Physical Review. B, Condensed Matter and Materials Physics, Journal Name: Physical Review. B, Condensed Matter and Materials Physics Journal Issue: 14 Vol. 92; ISSN 1098-0121

Publisher:: American Physical Society (APS)Copyright Statement

Country of Publication:: United States

Language:: English

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Title: Magnetic Correlations in the Quasi-Two-Dimensional Semiconducting Ferromagnet CrSiTe₃