Evidence for short-range antiferromagnetic fluctuations in Kondo-insulating YbB12

Abstract

The spin dynamics of mixed-valence YbB12 has been studied by inelastic neutron scattering on a high-quality single crystal. In the Kondo-insulating regime realized at low temperature, the spectra exhibit a spin-gap structure with two sharp, dispersive, in-gap excitations at E = 14.5 and approximately 20 meV. The lower mode is shown to be associated with short-range correlations near the antiferromagnetic wave vector q0 = (1/2, 1/2, 1/2). Its properties are in overall agreement with those expected for a "spin exciton'' branch in an indirect hybridization gap semiconductor.

4 pages, 4 figures ; submitted to Physical Review Letters

References in corpus (3)

• Optical conductivity of the Kondo insulator YbB_12: Gap formation and low-energy excitations
• Yb-Yb correlations and crystal-field effects in the Kondo insulator YbB12 and its solid solutions
• Short-range antiferromagnetic correlations in Kondo insulators

Cited by in corpus (18)

• Quantum Oscillations of Electrical Resistivity in an Insulator
• Multipolar phases and magnetically hidden order: Review of the heavy-fermion compound Ce(1-x)La(x)B6
• Resonant magnetic exciton mode in the heavy-fermion antiferromagnet CeB6
• Rattling mode and symmetry lowering resulting from instability of B${}_{12}$-molecule in LuB${}_{12}$
• Unconventional thermal metallic state of charge-neutral fermions in an insulator
• Another dimension: investigations of molecular magnetism using muon-spin relaxation
• muSR and inelastic neutron scattering investigations of the caged type Kondo semimetals: CeT2Al10 (T=Fe, Ru and Os)
• Theory of Spin Exciton in the Kondo Semiconductor $Yb{B}_{12}$
• Localized excitation in the hybridization gap in YbAl3
• Hall effect in the vicinity of quantum critical point in Tm1-xYbxB12
• Hall anomaly, Quantum Oscillations and Possible Lifshitz Transitions in Kondo Insulator YbB${}_{12}$: Evidence for Unconventional Charge Transport
• Dispersive magnetic resonance mode in the Kondo semiconductor CeFe2Al10
• Excitonic Bound State in the Extended Anderson Model with c-f Coulomb Interaction
• Topological surface states in the Kondo insulator YbB${}_{12}$ revealed via planar tunneling spectroscopy
• Robust hybridization gap in a Kondo Insulator YbB${}_{12}$ probed by femtosecond optical spectroscopy
• Theory for Magnetic Anisotropy of Field-Induced Insulator-to-Metal Transition in Cubic Kondo Insulator YbB_{12}
• The role of the short range magnetic correlations on the gap opening of the topological Kondo insulators
• Insulator-to-metal phase transition in Yb-based Kondo insulators