Molecular spin-liquid state in spin-3/2 frustrated spinel HgCr${}_2$O${}_4$

Abstract

A hexamer-type spin excitation seen in spinel chromates $A$Cr${}_2$O${}_4$ ($A$ = Mg, Zn, or Cd) is the representative spin-liquid-like state caused by geometrical frustration. To clarify an origin of the state, we comparatively studied spin excitations in an isomorphic material HgCr${}_2$O${}_4$ by inelastic neutron scattering, and observed a different molecular-type excitation. Numerical analyses performed using model Hamiltonians suggest that these two types of spin excitations originate from a spin-3/2 molecular singlet hidden in a magnetically ordered phase. The difference between the molecular types is explained by the difference in the kind of exchange interactions occurring in the chromates.

5 pages, 2 figures

References in corpus (4)

• Electronic band structure and exchange coupling constants in ACr2X4 spinels
• Pinwheel VBS state and triplet excitations in the two-dimensional deformed kagome lattice
• Molecular spin resonance in the geometrically frustrated MgCr2O4 magnet by inelastic neutron scattering
• Monte Carlo study of half-magnetization plateau and magnetic phase diagram in pyrochlore antiferromagnetic Heisenberg model

Cited by in corpus (13)

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• Berezinskii-Kosterlitz-Thouless Type Scenario in Molecular Spin Liquid $A$Cr${}_2$O${}_4$
• Neutron Scattering Studies of the Breathing Pyrochlore Antiferromagnet LiGaCr${}_4$O${}_8$
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• Neutron Diffraction Evidence for Local Spin Canting, Weak Jahn-Teller Distortion, and Magnetic Compensation in Ti${}_{1-x}$Mn${}_x$Co${}_2$O${}_4$ Spinel
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• Inelastic Neutron Scattering Study of the Spin Dynamics in the Breathing Pyrochlore System LiGa0.95In0.05Cr4O8
• Dynamic Spin-Lattice Coupling and Statistical Interpretation for the Molecular-Like Excitations in Frustrated Pyrochlores
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