Probing critical spin fluctuations with a composite magnetoelectric method: A case study on a Kitaev spin liquid candidate Na${}_3$Co${}_2$SbO${}_6$

Abstract

In correlated quantum materials, divergent critical fluctuations near the quantum critical point are often closely associated with exotic quantum phases of matter, such as unconventional superconductivity and quantum spin liquids. Here we present a simple yet highly sensitive composite magnetoelectric (ME) method for detecting the critical spin fluctuations in quantum magnets. The ME signal is proportional the magnetostriction coefficient, which directly probes the product of magnetization and spin-spin correlation. As a demonstration, the composite ME method is applied to a Kitaev quantum spin liquid candidate Na${}_3$Co${}_2$SbO${}_6$, which shows signs of magnetic field-induced quantum criticality. Notably, the ME signal prominently diverges at the magnetic field-induced tricritical points, particularly at a tricritical point that lies in close proximity to a zero-temperature quantum critical point. A crucial aspect of these tricritical points is their tunability through the modification of the in-plane magnetic field's direction. The direction of magnetic field can thus serve as a handful yet important tuning parameter, alongside pressure and chemical doping, for searching quantum critical points in quantum magnets with pronounced magnetic anisotropy.

6 pages, 4 figures

References in corpus (21)

• "Deconfined" quantum critical points
• $\alpha$-RuCl3: a Spin-Orbit Assisted Mott Insulator on a Honeycomb Lattice
• Quantum criticality
• On the Origin of Zigzag Magnetic Order in Iridium Oxide Na2IrO3
• Magnetization processes of zigzag states on the honeycomb lattice: Identifying spin models for $\alpha$-RuCl${}_3$ and Na${}_2$IrO${}_3$
• Kitaev interactions in the Co honeycomb antiferromagnets Na${}_3$Co${}_2$SbO${}_6$ and Na${}_2$Co${}_2$TeO${}_6$
• A.C. susceptibility as a probe of low-frequency magnetic dynamics
• Weak-field induced nonmagnetic state in a Co-based honeycomb
• Magnetic order in single crystals of Na3Co2SbO6 with a honeycomb arrangement of 3d${}^7$ Co${}^{2+}$ ions
• Excitations in the ordered and paramagnetic states of honeycomb magnet Na2Co2TeO6
• High resolution magnetostriction measurements in pulsed magnetic fields using Fibre Bragg Gratings
• Dominant Kitaev interactions in the honeycomb materials Na${}_3$Co${}_2$SbO${}_6$ and Na${}_2$Co${}_2$TeO${}_6$
• A magnetic continuum observed by terahertz spectroscopy in a quantum spin liquid candidate BaCo${}_2$(AsO${}_4$)${}_2$
• Giant magnetic in-plane anisotropy and competing instabilities in Na3Co2SbO6
• Synthesis, structure and magnetic properties of honeycomb-layered Li3Co2SbO6 with new data on its sodium precursor, Na3Co2SbO6
• Magnetic excitations of the field induced states in BaCo2(AsO4)2 probed by time-domain terahertz spectroscopy
• Magnetic phase diagram and possible Kitaev-like behavior of honeycomb-lattice antimonate Na3Co2SbO6
• Easy-plane multi-$\mathbf{q}$ magnetic ground state of Na${}_3$Co${}_2$SbO${}_6$
• Magnetoelastic couplings in the deformed Kagomé quantum spin lattice of volborthite
• Observation of enhanced spin-spin correlations at triple point in 2D ferromagnetic Cr2X2Te6 (X=Si, Ge)
• Field-induced phase transitions and quantum criticality in a honeycomb antiferromagnet Na3Co2SbO6

Cited by in corpus (2)

• Field-induced magnetic phases in the Kitaev candidate Na${}_3$Co${}_2$SbO${}_6$
• Anisotropic magnetoelastic coupling in the honeycomb magnet Na${}_3$Co${}_2$SbO${}_6$