Speaker
Description
Skyrmions are topologically protected spin vortices in the nanometre scale that behave like particles. In chiral crystals, competing magnetic interactions may induce 2D skyrmion lattices [1-2]. In the multiferroic insulator Cu$_2$OSeO$_3$, the skyrmion lattice responds to electric/magnetic fields suggesting applications in data storage [3]. These applications crucially depend on the stability conditions of the skyrmion phase. Notably, Cu$_2$OSeO$_3$ is the only material in which the appearance of two different skyrmion phases has been reported in its phase diagram. However, the quantum mechanisms of these phases and their thermodynamic connection are still under debate [4-6]. Hence, we used Small Angle Neutron Scattering and Lorentz Transmission Electron Microscopy to study the skyrmion stabilisation in single crystals of Cu$_2$OSeO$_3$ [7]. In this work, we report the field, temperature, and sample alignment dependence of the scaling behaviour of skyrmions as an order parameter for the emergence of the two skyrmion phases.
[1] S. Muehlbauer et al., Science 323, 915 (2009)
[2] S. Seki, X. Z. Yu, S. Ihiwata, and Y. Tokura, Science 336, 198 (2009)
[3] A. Fert, N. Reyren, V. Cros, Nat. Rev. Mats. 2, 01731 (2017)
[4] A. Chacon, L. Heinen et al., Nat. Phys. 14, 936-941 (2018)
[5] F. Qian, L. J. Bannenberg et al., Sci. Adv. 4, eaat7323 (2018)
[6] L. J. Bannenberg, H. Wilhelm et al., npj Quantum Mater. 4, 11 (2019)
[7] M.-G. Han, et al., Sci. Adv. 6, eaax2138 (2020)
| Presenter Gender | Man |
|---|---|
| Do you wish to take part in the Student Poster Slam | No |
| Level of Expertise | Student |
| Which facility did you use for your research | Australian Centre for Neutron Scattering |
| Condition of submission | Yes |
| Students Only - Are you interested in AINSE student funding | Yes |
