Field-angle resolved magnetic excitations as a probe of hidden-order symmetry in CeB6

Abstract

In contrast to magnetic order formed by electrons' dipolar moments, ordering phenomena associated with higher-order multipoles (quadrupoles, octupoles, etc.) are more difficult to characterize because of the limited choice of experimental probes that can distinguish different multipolar moments. The heavy-fermion compound CeB6 and its La-diluted alloys are among the best-studied realizations of the long-range-ordered multipolar phases, often referred to as "hidden order". Previously the hidden order in phase II was identified as primary antiferroquadrupolar (AFQ) and field-induced octupolar (AFO) order. Here we present a combined experimental and theoretical investigation of collective excitations in the phase II of CeB6. Inelastic neutron scattering (INS) in fields up to 16.5 T reveals a new high-energy mode above 14 T in addition to the low-energy magnetic excitations. The experimental dependence of their energy on the magnitude and angle of the applied magnetic field is compared to the results of a multipolar interaction model. The magnetic excitation spectrum in rotating field is calculated within a localized approach using the pseudo-spin presentation for the Gamma8 states. We show that the rotating-field technique at fixed momentum can complement conventional INS measurements of the dispersion at constant field and holds great promise for identifying the symmetry of multipolar order parameters and the details of inter-multipolar interactions that stabilize hidden-order phases.

arXiv comment15 pages with 13 figures + Supplemental Material

References in corpus (35)

• The new Cold Neutron Chopper Spectrometer at the Spallation Neutron Source - Design and Performance
• HORACE: software for the analysis of data from single crystal spectroscopy experiments at time-of-flight neutron instruments
• Emergent Rank-5 'Nematic' Order in URu2Si2
• Antiferro-quadrupole Ordering of CeB${}_6$ Studied by Resonant X-ray Scattering
• Description of Multipole in f-Electron Systems
• Chirality density wave of the 'hidden order' phase in URu${}_2$Si${}_2$
• A quantum liquid of magnetic octupoles on the pyrochlore lattice
• Ferroquadrupole ordering and Gamma_5 rattling motion in clathrate compound Ce_3Pd_20Ge_6
• The Cold Neutron Chopper Spectrometer at the Spallation Neutron Source - A Review of the first 8 Years of Operation
• Intertwined dipolar and multipolar order in the triangular-lattice magnet TmMgGaO${}_4$
• Multipolar phases and magnetically hidden order: Review of the heavy-fermion compound Ce(1-x)La(x)B6
• Detection of Neutron Scattering from Phase IV of Ce0.7La0.3B6: A Confirmation of the Octupole Order
• Resonant magnetic exciton mode in the heavy-fermion antiferromagnet CeB6
• Intense low-energy ferromagnetic fluctuations in the antiferromagnetic heavy-fermion metal CeB6
• Magnetic-Field-Induced 4f-Octupole in CeB6 Probed by Resonant X-ray Diffraction
• Gains from the upgrade of the cold neutron triple-axis spectrometer FLEXX at the BER-II reactor
• A theory of the electric quadrupole contribution to resonant x-ray scattering: Application to multipole ordering phases in Ce_{1-x}La_{x}B_{6}
• Spin Exciton Formation inside the Hidden Order Phase of CeB6
• Resonant X-Ray Scattering from the Quadrupolar Ordering Phase of CeB_6
• Broken symmetries in URu2Si2
• Spin-Orbital Wave Excitations in Orbitally Degenerate Exchange Model with Multipolar Interactions
• Multipole fluctuation theory for heavy fermion systems: Application to multipole orders in CeB6
• Evolution of the multiband RKKY interaction: Application to iron pnictides and chalcogenides
• Derivation of RKKY Interaction between Multipole Moments in CeB${}_6$ by the Effective Wannier Model based on the Bandstructure Calculation
• Ordered Phases and Quantum Criticality in Cubic Heavy Fermion Compounds
• The quartet ground state in CeB${}_6$: an inelastic x-ray scattering study
• Doping-induced redistribution of magnetic spectral weight in substituted hexaborides Ce${}_{1-x}$La${}_x$B${}_6$ and Ce${}_{1-x}$Nd${}_x$B${}_6$
• Magnetic resonance in cerium hexaboride caused by quadrupolar ordering
• Incommensurate short-range multipolar order parameter of phase II in Ce3Pd20Si6
• Search for Multipolar Instability in URu${}_2$Si${}_2$ Studied by Ultrasonic Measurements under Pulsed Magnetic Field
• Magnetic-field and doping dependence of low-energy spin fluctuations in the antiferroquadrupolar compound Ce(1-x)La(x)B(6)
• Magnetic field dependence of the neutron spin resonance in CeB6
• Evolution of the propagation vector of antiferroquadrupolar phases in Ce3Pd20Si6 with magnetic field
• Collective spin resonance excitation in the gapped itinerant multipole hidden order phase of URu2Si2
• Multipolar order and excitations in rare-earth boride Kondo systems

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