Our research in this field aims to unravel the physics of topologically protected structures arising in correlated matter like skyrmions and ferroelectric domain-wall vortex cores, both promising new functionalities of correlated matter that could pave the way for future advances in microelectronics.

Skyrmions, whirl-like spin objects, in recent years have attracted tremendous interest from both an academic and technological point of view. We search for new types of skyrmion-lattice states that are stable in a large parameter space. Moreover, we explore multiferroic skyrmion systems that may enable the dissipation-free electronic control of these nanometer-sized objects, which is crucial for skyrmion-based memory devices.

We also investigate vortex-like ferroelectric domain patterns, where the vortex cores represent stable topological defects, as occurring in hexagonal manganites. These stable topological objects may be of high relevance for the design of new domain-wall-based microelectronic devices.

Skyrmion systems

• Ferroelectric skyrmions in GaV₄S₈

Domain-wall vortex cores

• YMnO3 - Conductivity of vortex-like domain patterns         

Some relevant publications from our group:

• Néel-type skyrmion lattice with confined orientation in the polar magnetic semiconductor GaV₄S₈
  I. Kézsmárki, S. Bordács, P. Milde, E. Neuber, L. M. Eng, J. S. White, H. M. Ronnow, C. D. Dewhurst, M. Mochizuki, K. Yanai, H. Nakamura, D. Ehlers, V. Tsurkan, and A. Loidl
  Nature Materials, 14, 1116 (2015)
• Multiferroicity and skyrmions carrying electric polarization in GaV₄S₈
  E. Ruff, S. Widmann, P. Lunkenheimer, V. Tsurkan, S. Bordács, I. Kézsmárki, and A. Loidl
  Science Advances, 1, E1500916 (2015)
• Conductivity Contrast and Tunneling Charge Transport in the Vortexlike Ferroelectric Domain Patterns of Multiferroic Hexagonal YMnO₃
  E. Ruff, S. Krohns, M. Lilienblum, D. Meier, M. Fiebig, P. Lunkenheimer, and A. Loidl
  Phys. Rev. Lett. 118, 036803 (2017)
• Characteristics of ferroelectric-ferroelastic domains in Néel-type skyrmion host GaV₄S₈
  A. Butykai, S. Bordács, I. Kézsmárki, V. Tsurkan, A. Loidl, J. Döring, E. Neuber, P. Milde, S. C. Kehr, and L. M. Eng
  Scientific Report 7, 44663 (2017)
• Equilibrium Skyrmion Lattice Ground State in a Polar Easy-Plane Magnet
  S. Bordács, A. Butykai, B. G. Szigeti, J. S. White, R. Cubitt, A. O. Leonov, S. Widmann, D. Ehlers, H.-A. Krug von Nidda, V. Tsurkan, A. Loidl, and I. Kézsmárki
  Scientific Report 7, 7584 (2017)