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Updated: May 31, 2026

Spectral and Angle-Resolved Magneto-Optical Characterization of Photonic Nanostructures
Published on: November 21, 2019
The observation of magnetic excitations in a single layered and a bilayered brownmillerite
Stephen J Blundell1, John A Stride, Michael L Brooks
1Department of Physics, Clarendon Laboratory, Oxford University, Parks Road, Oxford OX1 3PU, UK.
Abstract:
We describe the results of an inelastic neutron scattering measurement of the magnetic excitations in SrCaGaMnO(5+δ), a quasi-two-dimensional compound whose structure consists of layers of MnO(6) octahedra separated by layers of GaO(4) tetrahedra (the brownmillerite structure), and Ca(2.5)Sr(0.5)Mn(2)GaO(8), a bilayered brownmillerite. In both materials, a band of magnetic scattering appears below the magnetic ordering temperature which can be associated with magnon excitations. Our measurements allow us to provide an estimate for the intraplane exchange constant in both materials, which we find to be 3.4(4) meV for SrCaGaMnO(5+δ) and 2.2(4) meV for Ca(2.5)Sr(0.5)Mn(2)GaO(8).
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