Effect of structural disorder on the Kitaev magnet Ag${}_3$LiIr${}_2$O${}_6$

Abstract

Searching for an ideal Kitaev spin liquid candidate with anyonic excitations and long-range entanglement has motivated the synthesis of a new family of intercalated Kitaev magnets such as H${}_3$LiIr${}_2$O${}_6$, Cu${}_2$IrO${}_3$, and Ag${}_3$LiIr${}_2$O${}_6$. The absence of a susceptibility peak and a two-step release of the magnetic entropy in these materials has been proposed as evidence of proximity to the Kitaev spin liquid. Here we present a comparative study of the magnetic susceptibility, heat capacity, and muon spin relaxation ($\mu$SR) between two samples of Ag${}_3$LiIr${}_2$O${}_6$ in the clean and disordered limits. In the disordered limit, the absence of a peak in either susceptibility or heat capacity and a weakly depolarizing $\mu$SR signal may suggest a proximate spin liquid ground state. In the clean limit, however, we resolve a peak in both susceptibility and heat capacity data, and observe clear oscillations in $\mu$SR that confirm long-range antiferromagnetic ordering. The $\mu$SR oscillations fit to a Bessel function, characteristic of an incommensurate order, as reported in the parent compound $\alpha$-Li${}_2$IrO${}_3$. Our results clarify the role of structural disorder in the intercalated Kitaev magnets.

8 pages, 9 figures

References in corpus (3)

• Mott Insulators in the Strong Spin-Orbit Coupling Limit: From Heisenberg to a Quantum Compass and Kitaev Models
• $\alpha$-RuCl3: a Spin-Orbit Assisted Mott Insulator on a Honeycomb Lattice
• Thermodynamic Evidence of Proximity to a Kitaev Spin-Liquid in Ag${}_3$LiIr${}_2$O${}_6$

Cited by in corpus (7)

• Experimental signatures of quantum and topological states in frustrated magnetism
• Nearly itinerant electronic groundstate in the intercalated honeycomb iridate Ag${}_3$LiIr${}_2$O${}_6$
• First demonstration of tuning between the Kitaev and Ising limits in a honeycomb lattice
• Quantum paramagnetism in the hyperhoneycomb Kitaev magnet $\beta$-ZnIrO${}_3$
• Disorder-induced excitation continuum in a spin-1/2 cobaltate on a triangular lattice
• Role of disorder in the electronic and magnetic properties of Ag${}_3$LiIr${}_2$O${}_6$
• Pressure tuning of competing interactions on a honeycomb lattice