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arXiv · 2312.04834

Field-induced phase transitions and anisotropic magnetic properties of the Kiteav-Heisenberg compound Na$_2$Co$_2$TeO$_6$

A. K. Bera·S. M. Yusuf·F. Orlandi·P. Manuel·L. Bhaskaran·S. A. Zvyagin
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Abstract

Spin systems with honeycomb structures have recently attracted a great deal of attention in connection with the Kitaev quantum spin liquid state (QSL) predicted theoretically. One possible Kitaev QSL candidate is Na$_2$Co$_2$TeO$_6$ realizing a honeycomb lattice of pseudo-spin-1/2. Field-dependent single-crystal neutron diffraction technique allows us to determine the microscopic spin-spin correlations across the field induced phase transitions for H//a and H//a* in plane field directions. Our results reveal phase transitions, initially to a canted zigzag antiferromagnetic state at approximately 60 kOe, followed by a possible transition to a partially polarized state over the range of 90-120 kOe, and finally to a field-induced fully polarized state above 120 kOe. We observe distinct field dependencies of the magnetic peak intensities for H//a and H//a*. In addition, low-temperature electron spin resonance in magnetic fields H//c yields a complete softening for one of the antiferromagnetic resonances at ~ 40 kOe, revealing a field-induced phase transition. The present work, thus, provides new insights into the field evolution of the important Kitaev-Heisenberg spin system Na$_2$Co$_2$TeO$_6$.

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A. K. Bera, S. M. Yusuf, F. Orlandi, P. Manuel, L. Bhaskaran, S. A. Zvyagin. 2023-12-08. Field-induced phase transitions and anisotropic magnetic properties of the Kiteav-Heisenberg compound Na$_2$Co$_2$TeO$_6$. https://arxiv.org/abs/2312.04834

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