Magnetic phase transition in YCo3B2 studied by magnetic resonance

Abstract

Magnetic-susceptibility measurements, nuclear magnetic resonance (NMR) of B11, and electron magnetic-resonance (EMR) spectra of YCo3B2 were measured as a function of the temperature. The temperature dependence of the magnetic susceptibility showed a lambda-shaped anomaly at 150K. Whereas upon cooling, a shift in the resonance position of the NMR and EMR spectra is observed at 150K, marking the emergence of an internal magnetic field. The quadrupolar splitting of the NMR lines showed a marked discontinuity at 150K. The (T1T)−1∕2 values were found to be independent of temperature for T>175K, and to increase sharply upon cooling for T<150K. The intensity of the EMR line which is independent of temperature for T>160K is also found to increase markly upon cooling below 150K. All these effects are discussed and it is proposed that YCo3B2 undergoes a magnetic ordering phase transition at 150K.

Magnetic properties and magnetocaloric effect in GdCo3B2 compound

“…These behaviours were consistent with previous reported results by Ido et al [16] and similar with those in TbCo 3 B 2 [14,17]. Sigalov et al [18] studied the magnetic phase transition in YCo 3 B 2 by nuclear magnetic resonance and electron resonance spectra, and they concluded that Co sublattice in RCo 3 B 2 orders at 150 (20) K independent of rare earth element Dubman et al [14] further confirmed this behaviour in TbCo 3 B 2 by means of neutron diffraction method, i.e. the observed lower temperature transition (∼54 K) and the anomaly change (∼160 K) in GdCo 3 B 2 were corresponding to the Gd-Gd sub-lattice and the Co-Co sub-lattice magnetic ordering transition, respectively.…”

“…The RCo 3 B 2 compounds are paramagnetic at room temperature and undergo a Co-Co sublattice magnetic order transition at ∼160 (20) K. In addition, a second R-R sublattice magnetic order transition was also observed at 54, 47, 28 and 22 K for R = Gd, Sm, Tb and Dy, respectively [12][13][14][15][16][17][18][19]. Among all the rare-earth transition metal compounds, Gd-based systems [20][21][22] have been extensively investigated owning to that Gd ion has the largest spinorial moment and has the highest effective exchange coupling around room temperature.…”

“…The ternary intermetallic compounds of the RCo 3 B 2 where R is a rare earth or yttrium have attracted some attentions due to their interesting physical properties [12][13][14][15][16][17][18][19]. The RCo 3 B 2 compounds are paramagnetic at room temperature and undergo a Co-Co sublattice magnetic order transition at ∼160 (20) K. In addition, a second R-R sublattice magnetic order transition was also observed at 54, 47, 28 and 22 K for R = Gd, Sm, Tb and Dy, respectively [12][13][14][15][16][17][18][19].…”

Magnetic and crystallographic study of Tb0.75Y0.25Co3B2

“…1). The high temperature anomaly was also found at similar temperature in the susceptibility and magnetization measurements of the undoped TbCo 3 B 2 [4] and YCo 3 B 2 [5], where it was attributed to the ferromagnetic ordering temperature, T C . Thus, the present ac susceptibility measurement suggests that the magnetic ordering temperature, T C , of Tb 0.75 Y 0.25 Co 3 B 2 did not change as a result of Y doping, as expected.…”

“…In addition, below T SRT a symmetry decrease sets in, leading to an orthorhombic distortion of the crystal lattice. Attributing the high temperature transition to the Co-Co exchange interaction was supported by the study of YCo 3 B 2 [5] where only the T C transition was observed. In order to study the T SRT dependence on the magnetic properties of the R-atom, we chose to study the magnetic and crystallographic properties of the solid solution Tb 0.75 Y 0.25 Co 3 B 2 .…”