Possible spin-orbit driven spin-liquid ground state in the double perovskite phase of Ba3YIr2O9

Abstract

We report the structural transformation of hexagonal Ba3YIr2O9 to a cubic double perovskite form (stable in ambient conditions) under an applied pressure of 8GPa at 1273K. While the ambient pressure (AP) synthesized sample undergoes long-range magnetic ordering at 4K, the high pressure(HP) synthesized sample does not order down to 2K as evidenced from our susceptibility, heat capacity and nuclear magnetic resonance (NMR) measurements. Further, for the HP sample, our heat capacity data have the form gamma*T+beta*T3 in the temperature (T) range of 2-10K with the Sommerfeld coefficient gamma=10mJ/mol-Ir K2. The 89Y NMR shift has no T-dependence in the range of 4-120K and its spin-lattice relaxation rate varies linearly with T in the range of 8-45K (above which it is T-independent). Resistance measurements of both the samples confirm that they are semiconducting. Our data provide evidence for the formation of a 5d based, gapless, quantum spin-liquid (QSL) in the cubic (HP) phase of Ba3YIr2O9. In this picture, the T term in the heat capacity and the linear variation of 89Y 1/T1 arises from excitations out of a spinon Fermi surface. Our findings lend credence to the theoretical suggestion [G. Chen, R. Pereira, and L. Balents, Phys. Rev. B 82, 174440 (2010)] that strong spin-orbit coupling can enhance quantum fluctuations and lead to a QSL state in the double perovskite lattice.

6 pages 5 figures

References in corpus (5)

• Novel Jeff = 1/2 Mott State Induced by Relativistic Spin-Orbit Coupling in Sr2IrO4
• Spin-Liquid State in the S = 1/2 Hyperkagome Antiferromagnet Na4Ir3O8
• High pressure sequence of Ba_3NiSb_2O_9 structural phases: new $S=1$ quantum spin-liquids based on Ni^{2+}
• Spin liquid behaviour in Jeff=1/2 triangular lattice Ba3IrTi2O9
• Weak magnetic transitions in pyrochlore Bi2Ir2O7

Cited by in corpus (16)

• Models and Materials for Generalized Kitaev Magnetism
• Ba2YIrO6: A cubic double perovskite material with Ir5+ ions
• Persistent low-temperature spin dynamics in the mixed-valence iridate Ba${}_3$InIr${}_2$O${}_9$
• Local Magnetism and Spin Dynamics of the Frustrated Honeycomb Rhodate Li2RhO3
• Magnetism out of disorder in a J=0 compound Ba2YIrO6
• Ba${}_3$M${}_x$Ti${}_{3-x}$O${}_9$(M = Ir, Rh): A family of 5\textit{\textcolor{black}{d}}/4\textit{\textcolor{black}{d}}-based, diluted quantum spin liquids
• Instabilities of Spin-Liquid States in a Quantum Kagome Antiferromagnet
• Unconventional magnetism in the spin-orbit driven Mott insulators Ba3MIr2O9 (M=Sc,Y)
• Quantum Spin Liquid State in the Disordered Triangular Lattice Sc2Ga2CuO7
• Unconventional magnetism in the 4d${}^4$ based ($S=1$) honeycomb system Ag${}_3$LiRu${}_2$O${}_6$
• Spin-orbit effects in pentavalent Iridates: Models and materials
• Electronic structure and magnetic properties of 3d-4f double perovskite material
• Sc_{2}Ga_{2}CuO_{7}: A possible Quantum spin liquid near the percolation threshold
• Magnetization dynamics fingerprints of an excitonic condensate $t_{2g}^4$ magnet
• J = 0 nonmagnetic insulating state in K${}_2$Os$X_6$ (X = F, Cl and Br)
• Collapse of susceptibility and non-trivial spin dynamics in the hyper-honeycomb magnet $\beta$-Li${}_2$IrO${}_3$ under high pressure