Field-induced magnetic incommensurability in multiferroic Ni3TeO6
Research output: Contribution to journal › Journal article › Research › peer-review
53 Downloads (Pure)
Using single-crystal neutron diffraction we show that the magnetic structure Ni3TeO6 at fields above 8.6 T along the c axis and low temperature changes from a commensurate collinear antiferromagnetic structure with spins along c and ordering vector QC=(001.5) to a conical spiral with propagation vector QIC=(001.5±δ), δ∼0.18, having a significant spin component in the (a,b) plane. We determine the phase diagram of this material in magnetic fields up to 10.5 T along c and show the phase transition between the low field and conical spiral phases is of first order by observing a discontinuous jump of the ordering vector. QIC is found to drift both as a function of magnetic field and temperature. Preliminary inelastic neutron-scattering data reveal that the spin-wave gap in zero field has minima exactly at QIC and a gap of about 1.1 meV consisting with a crossover around 8.6 T. Further, a simple magnetic Hamiltonian accounting in broad terms for these is presented. Our findings confirm the exclusion of the inverse Dzyaloshinskii-Moriya interaction as a cause for the giant magnetoelectric due to symmetry arguments. In its place we advocate for the symmetric exchange striction as the origin of this effect.
Lass, J., Andersen, C. R., Leerberg, H. K., Birkemose, S., Toth, S., Stuhr, U., Bartkowiak, M., Niedermayer, C., Lu, Z., Toft-Petersen, R., Retuerto, M., Birk, J. O., & Lefmann, K. (2020). Field-induced magnetic incommensurability in multiferroic Ni3TeO6. Physical Review B, 101(5), . https://doi.org/10.1103/physrevb.101.054415