Achieving the efficient use of electron spin for next-generation information technologies is a principal research aim for scientists in the field of spintronics. Spin waves in suitable materials can propagate over the length scale of millimetres with frequencies from GHz to even THz regimes and with a broad range of wavelengths from micrometres to nanometres. These properties can be controlled and tuned using an appropriate choice of magnetic materials, sample geometries, and excitation methods.
Materials suitable for spin transport tend to be chemically complex and challenging to synthesise, and few have been investigated. A recently-proposed approach is to use magnons, which are spin excitations in magnetically-ordered systems. In work published in Physical Review Materials, researchers from University College, London, and ISIS conducted a comprehensive analysis of the high-temperature crystal structure of the Swedenborgite CaBaFe4O7, a candidate for magnon transport. They collected single-crystal neutron-diffraction data with the single-crystal diffractometer (SXD), and additional data on the high-resolution powder diffractometer (HRPD).
They demonstrated that the growth of large crystals via the liquid phase is possible, opening the door to further investigations into the magnetic structure and dynamic response of this promising material.
Related publication: “Crystal structure and crystal growth of the polar ferrimagnet CaBaFe4O7" Phys. Rev. Materials, 2018, 2, 054403, DOI: 10.1103/PhysRevMaterials.2.054403
Authors: R. S. Perry (University College London; ISIS), H. Kurebayashi (University College London), A. Gibbs (ISIS), and M. J. Gutmann (ISIS).
Instrument: SXD and HRPD