Magnetic behavior of nanocrystals of the spin-chain system Ca₃Co₂O₆: absence of multiple steps in the low-temperature isothermal magnetization

Abstract

We report that the major features in the temperature dependence of dc and ac magnetizations of a well-known spin-chain compound Ca₃Co₂O₆, which has been known to exhibit two complex magnetic transitions due to geometrical frustration (one near 24 K and the other near 10 K), are found to be qualitatively unaffected in its nanomaterials synthesized by high-energy ball milling. However, the multiple steps in isothermal magnetization-a topic of current interest in low-dimensional systems-known for the bulk form well below 10 K is absent in the nanoparticles. We believe that this finding will be useful to the understanding of the "step" magnetization behavior of such spin-chain systems.