Evolution of the propagation vector of antiferroquadrupolar phases in ${\mathrm{Ce}}_3{\mathrm{Pd}}_{20}{\mathrm{Si}}_6$ under magnetic field

Journal Article · 24 June 2019 · Physical Review B

DOI: https://doi.org/10.1103/PhysRevB.99.214431 · OSTI ID:1531202

Portnichenko, P. Y. ^[1]; Nikitin, S. E. ^[2]; Prokofiev, A. ^[3]; Paschen, S. ^[3]; Mignot, Jean-Michel ^[4]; Ollivier, J. ^[5]; Podlesnyak, Andrey  ^[6]; Meng, Siqin ^[7]; Lu, Zhilun ^[8]; Inosov, Dmytro S. ^[1]

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1. Technische Univ. of Dresden (Germany)
2. Technische Univ. of Dresden (Germany); Max-Planck-Inst. für Chemische Physik fester Stoffe, Dresden (Germany)
3. Vienna Univ. of Technology (Austria). Inst. of Solid State Physics
4. Lab. Léon Brillouin, Gif sur Yvette (France)
5. Inst. Laue-Langevin, Grenoble (France)
6. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
7. China Inst. of Atomic Energy, Beijing (China); Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Berlin (Germany)
8. Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Berlin (Germany)

Hidden-order phases that occur in a number of correlated $$f$$-electron systems are among the most elusive states of electronic matter. Their investigations are hindered by the insensitivity of standard physical probes, such as neutron diffraction, to the order parameter that is usually associated with higher-order multipoles of the $$f$$ orbitals. The heavy-fermion compound Ce₃Pd₂₀Si₆ exhibits magnetically hidden order at subkelvin temperatures, known as phase II. Additionally, for magnetic field applied along the [001] cubic axis, another phase II′ was detected, but the nature of the transition from phase II to phase II′ remained unclear. Here we use inelastic neutron scattering to argue that this transition is most likely associated with a change in the propagation vector of the antiferroquadrupolar order from (111) to (100). Despite the absence of magnetic Bragg scattering in phase II′, its ordering vector is revealed by the location of an intense magnetic soft mode at the (100) wave vector, that is orthogonal to the applied field. At the II-II′ transition, this mode softens and transforms into quasielastic and nearly Q-independent incoherent scattering, which is likely related to the non-Fermi-liquid behavior recently observed at this transition. Our experiment also reveals sharp collective excitations in the field-polarized paramagnetic phase, after phase II′ is suppressed in fields above 4 T.

• Research Organization: Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
• Grant/Contract Number: AC05-00OR22725
• OSTI ID: 1531202
• Journal Information: Physical Review B, Journal Name: Physical Review B Journal Issue: 21 Vol. 99; ISSN 2469-9950; ISSN PRBMDO
• Publisher: American Physical Society (APS)Copyright Statement
• Country of Publication: United States
• Language: English