Magnetic phase diagram ofBa3CoSb2O9as determined by ultrasound velocity measurements

Abstract

Using high resolution sound velocity measurements we have obtained a very precise magnetic phase diagram of Ba3CoSb2O9 a material that is considered to be an archetype of the spin 1/2 triangular-lattice antiferromagnet. Results obtained for the field parallel to the basal plane (up to 18 T) show three phase transitions, consistent with predictions based on simple 2D isotropic Heisenberg models and previous experimental investigations. The phase diagram obtained for the field perpendicular to the basal plane clearly reveals an easy-plane character of this compound and in particular, our measurements show a single first order phase transition at Hc1 = 12.0 T which can be attributed to a spin-flop between an umbrella-type configuration and a coplanar V-type order where spins lie in a plane perpendicular to the ab-plane. A low temperatures softening of the lattice within some of the ordered phases is also observed and may be a result of residual spin fluctuations.

Anisotropic field-induced ordering in the triangular-lattice quantum spin liquid NaYbSe2

“…The overall shape of the phase diagram is in good agreement with results from classical Monte-Carlo simulations [64], apart from the low-field disordered regime. Similar H-T phase diagrams for H ⊥ c and H c are also reported for the effective spin-1 2 TLAF Ba 3 CoSb 2 O 9 [65,66]. In contrast to these, the field-induced magnetic transitions are highly anisotropic in NaYbSe 2 .…”

Field-induced magnetic transition and spin fluctuations in the quantum spin-liquid candidate CsYbSe2

“…Based on the magnetization and heat capacity results, in each other. Note that the dome feature for LRO is also found in other frustrated magnetic materials [41,42,60].…”

Frustrated spin- 12 molecular magnetism in the mixed-valence antiferromagnets Ba3MRu2O9Ziat1, Aczel2, Sinclair3 et al. 2017Phys. Rev. BSelf Cite314303View full textAdd to dashboardCite

“…The revised magnetic structure is then simply a collinear stripe phase, which has been predicted to arise for the quasi-2D triangular lattice when the NN and NNN in-plane exchange interactions are antiferromagnetic and comparable in magnitude [22]. These materials could therefore be considered to be the molecular magnet equivalents of isostructural compounds (for instance Ba 3 CoSb 2 O 9 [9][10][11][12][13]) where the Msite is magnetic and forms a quasi-2d triangular lattice, albeit with a more important NNN interaction strength.…”

“…Materials in this family with magnetic M -sites have been shown to exhibit quantum spin liquid behavior, in particular 6HB-Ba 3 NiSb 2 O 9 [1][2][3] and Ba 3 IrTi 2 O 9 [4] while others, Ba 3 CuSb 2 O 9 [5][6][7] and Ba 3 ZnIr 2 O 9 [8], exhibit possible quantum spin-orbital liquids. Furthermore, Ba 3 CoSb 2 O 9 has allowed for some of the first studies on the magnetization process of a truly triangular spin-1/2 antiferromagnet [9][10][11][12][13]. The flexibility of this crystal structure means that we are also at liberty to include magnetic 4d/5d transition metal Asite ions and thereby study spin dimers distributed on a triangular lattice with significant spin-orbit coupling and orbital hybridization.…”