Hidden magnetic frustration by quantum relaxation in anisotropic Nd-langasite

Virginie Simonet (1) , Rafik Ballou (1) , Julien Robert , Benjamin Canals (2) , Françoise Hippert (3) , Pierre Bordet (4) , Pascal Lejay (5) , Peter Fouquet (6) , Jacques Ollivier (6) , Daniel Braithwaite (7)

1 NEEL - MagSup - Magnétisme et Supraconductivité
2 NEEL - TMC - Théorie de la Matière Condensée
3 LMGP - Laboratoire des matériaux et du génie physique
4 NEEL - MRS - Matériaux, Rayonnements, Structure
5 NEEL - C2MA - Croissance Cristalline et MicroAnalyse
6 ILL - Institut Laue-Langevin
7 IMAPEC - Instrumentation, Material and Correlated Electrons Physics

The static and dynamic magnetic properties of the Nd$_3$Ga$_5$SiO$_{14}$ compound, which appears as the first materialization of a rare-earth kagome-type lattice, were re-examined, owing to contradictory results in the previous studies. Neutron scattering, magnetization and specific heat measurements were performed and analyzed, in particular by fully taking account of the crystal electric field effects on the Nd$^{3+}$ ions. One of the novel findings is that the peculiar temperature independent spin dynamics observed below 10~K expresses single-ion quantum processes. This would short-circuit the frustration induced cooperative dynamics, which would emerge only at very low temperature.

Domaines: Electrons fortement corrélés [cond-mat.str-el]

Virginie Simonet, Rafik Ballou, Julien Robert, Benjamin Canals, Françoise Hippert, et al.. Hidden magnetic frustration by quantum relaxation in anisotropic Nd-langasite. Physical Review Letters, 2008, 100, pp.237204. ⟨10.1103/PhysRevLett.100.237204⟩. ⟨hal-00266071v2⟩