Magnetoelectric and magnetoelastic couplings in the quantum spin liquid candidate Na₂Co₂TeO₆

In the recent decades, the exactly solvable Kitaev model with its bond-dependent interactions has attracted large attention in the scientific community due to the promising features for quantum computing technologies [1]. However, to date there is no direct, purely bond-dependent realization of the Kitaev model among crystalline compounds, as all candidate materials have significant exchange interactions and long-range magnetic order as a result. While these interactions are undesirable, they have led to numerous interesting phenomena, as well as they also offer unique possibilities to suppress the long-range order. As an example, the magnetoelastic coupling in some Heisenberg-Kitaev magnets could be used to suppress the AFM order via uniaxial stress [2].

In this talk, we discuss the magnetoelastic and magnetoelectric properties of the quantum spin liquid candidate Na₂Co₂TeO₆. We study the phase diagram of Na₂Co₂TeO₆ using thermodynamic, magnetic, magnetoelastic, and magnetoelectric measurement techniques. We find strong magnetoelastic responses, particularly for in-plane fields are very sensitive indicators of phase transitions, and moderate magnetoelectric response. We contemplate the possibility of using magnetoelectricity in Heisenberg-Kitaev magnets as a new, unique way to extinguish the unwanted long-range order.

[1] A. Kitaev, Annals of Physics 321, 2 (2006)

[2] D. A. S. Kaib, S. Biswas, K. Riedl, S. M. Winter, and R. Valentí, Phys. Rev. B 103, L140402 (2021).