Field-induced spin-structural transition and giant magnetostriction in Ising chain $\alpha$-CoV${}_2$O${}_6$

Abstract

We have investigated the temperature and magnetic field dependence of magnetization, specific heat ($C_p$), and relative sample length change ($\Delta L/L_0$) for understanding the field-induced spin-structural change in quasi-one-dimensional spin chain $\alpha$-CoV${}_2$O${}_6$ which undergoes antiferromagnetic (AFM) transition below $T_N$$=$15 K. Analysis of $C_p$($T$) shows that an effective $S$$=$1/2 Ising state is realized below 20 K, though the magnetic fluctuations persist well above $T_N$. $C_p$ and the coefficient of linear thermal expansion ($\alpha$) exhibit strong $H$ dependence in the AFM state. We also observe a huge positive magnetostriction [$\Delta L$($H$)/$L_0$] below 20 K which does not show any tendency of saturation up to 9 T. With increasing field, a sharp and symmetric peak emerges below $T_N$ in both $C_p$($T$) and $\alpha$($T$) due to field-induced first order ferrimagnetic/ferromagnetic-paramagnetic transitions. The large value of magnetostriction below $T_N$ suggests strong spin-lattice coupling in $\alpha$-CoV${}_2$O${}_6$.

19 pages, 11 Figures Accepted for publication in J. Phys. Chem. C

References in corpus (5)

• Quantum criticality in an Ising chain: experimental evidence for emergent E8 symmetry
• Kagomé ice state in the dipolar spin ice Dy_{2}Ti_{2}O_{7}
• Novel ordering of an S = 1/2 quasi one-dimensional Ising-like anitiferromagnet in magnetic field
• Exactly solvable Ising--Heisenberg chain with triangular XXZ-Heisenberg plaquettes
• Phase transitions and thermodynamics of the two-dimensional Ising model on a distorted Kagomé lattice