PIRSA:14050026

Exotic Magnetism on the FCC Lattice of 5dn Double Perovskites

APA

Kermarrec, E. (2014). Exotic Magnetism on the FCC Lattice of 5dn Double Perovskites. Perimeter Institute for Theoretical Physics. https://pirsa.org/14050026

MLA

Kermarrec, Edwin. Exotic Magnetism on the FCC Lattice of 5dn Double Perovskites. Perimeter Institute for Theoretical Physics, May. 01, 2014, https://pirsa.org/14050026

BibTex

          @misc{ scivideos_PIRSA:14050026,
            doi = {10.48660/14050026},
            url = {https://pirsa.org/14050026},
            author = {Kermarrec, Edwin},
            keywords = {},
            language = {en},
            title = {Exotic Magnetism on the FCC Lattice of 5dn Double Perovskites},
            publisher = {Perimeter Institute for Theoretical Physics},
            year = {2014},
            month = {may},
            note = {PIRSA:14050026 see, \url{https://scivideos.org/pirsa/14050026}}
          }
          

Edwin Kermarrec McMaster University

Talk numberPIRSA:14050026
Talk Type Conference

Abstract

In the search for new exotic quantum states, the impact of strong spin-orbit interaction has been recently underlined with the discovery of the Jeff = ½ spin orbital Mott state in the 5d5 layered perovskites iridates [1]. The double perovskite structure, where the magnetic ions form a face-centered-cubic (fcc) sublattice, can accommodate a large variety of 5d transition metal elements, and therefore offers an ideal playground for systematic studies of the exotic magnetic and non-magnetic ground states stabilized by strong spin-orbit coupling [2]. Here, we report time-of-flight neutron scattering measurements on the antiferromagnetic, frustrated, cubic double perovskite system Ba2YOsO6. Its non-distorted fcc lattice is decorated with magnetic Os5+ (5d3) ions which undergo a magnetic transition to a long range ordered antiferromagnetic state below TN = 70 K, as revealed by magnetic Bragg peaks occuring at the [100] and [110] positions. Our inelastic data reveals a large spin gap to the spin-wave excitations Δ = 19(2) meV, unexpected for an orbitally quenched, d3 electronic configuration. We compare this result to the recent observation of a Δ=5 meV spin gap in the related cubic double perovskite Ba2YRuO6 (Ru5+, 4d3) [3], and conclude to a stronger spin-orbit coupling present in the heavier, 5d, osmate system.

[1] B. J. Kim et al., Science 323, 1329 (2009).
[2] G. Chen, R. Pereira and L. Balents, Phys. Rev. B 82, 174440 (2010);
G. Chen and L. Balents, Phys. Rev. B 84, 094420 (2011).
[3] J. P. Carlo et al., Phys. Rev. B 88, 024418 (2013).