Magnetic field influence on the Néel, dimer, and spin-liquid states of the low-dimensional antiferromagnetsNiTa2O6andCoSb2

A. B. Christian

¹

,

Sueli H. Masunaga

²

,

Aaron Schye

³

et al.

Abstract

Magnetic susceptibility and heat capacity measurements are used to infer information about the short-range magnetic order above the Néel temperature T N and the antiferromagnetically ordered states below T N of quasione-dimensional (quasi-1D) CuSb 2 O 6 , NiTa 2 O 6 , and CoSb 2 O 6 . It is shown that two antiferromagnetic sublattices, oriented at 90 • to one another, are likely present in NiTa 2 O 6 and CoSb 2 O 6 . Application of magnet field parallel to the quasi-1D chains of one sublattice is perpendicular to the chains of the other sublattice. This results in two antiferromagnetic transitions when the magnetic field H 2 T (∼0.2 meV). The anisotropic influence of magnetic field on the antiferromagnetic state leads to a magnetocaloric effect that is fully investigated in this work. The effect is associated with competition among Néel, dimer, and spin-liquid states that are all present at T N .

Torque magnetometry study of magnetically ordered state and spin reorientation in the quasi-one-dimensionalS=12Heisenberg antiferromagnetCuSb2O6Herak1, Žilić2, Čalogović3 et al. 2015Phys. Rev. B9040View full textAdd to dashboardCite

“…The orientation of (7) • , in good agreement with previously published data [1]. Presence of multiple twins, reported by other authors [2][3][4][12][13][14], was also observed in our data.…”

“…The symmetry of this anisotropy energy is higher than required for monoclinic CuSb 2 O 6 . In more recent papers by the same authors on, presumably, same samples the decrease of χ a was significantly smaller than of χ b [13] and some twinning of the samples was reported [14]. The polishing of the surface which was used to detwin the samples in Ref.…”

“…Large decrease of susceptibility characteristically observed when magnetic field is applied along the easy axis has been reported for b axis direction [4,11], a axis direction [3], and even for both directions [9,12,13]. Recent report on single crystal measurements of magnetic susceptibility showed that significant decrease of susceptibility below T N and spin flop transition at H SF = 1.25 T is observed when magnetic field is applied along both the a and b axis, suggesting that both a and b are the easy axes in CuSb 2 O 6 [12].…”

Local and long-range magnetic order of thespin−32systemCoSb2O6

“…7 Their low-dimensional magnetic behavior is evident from experiments [8][9][10][11][12] and electronic structure calculations. 13,14 In the case of CuSb 2 O 6 , orbital order is believed to promote antiparallel ordering of the magnetic moments along the [110] direction at z = 0 and the [110] direction at z = 1/2, which is commonly referred to as the two-sublattice antiferromagnetic structure.…”

“…The fact that some of these compounds can possess one dimensional (1D) chains that are weakly coupled to one another was proven through observations of an anisotropic magnetocaloric effect (MCE) 12 in NiTa 2 O 6 and CoSb 2 O 6 . The MCE is manifested as a downward shift of the peak in heat capacity C P with application of magnetic field H. If H is applied parallel to the 1D chains of one sublattice, it is then perpendicular to the 1D chains of the second sublattice.…”