Influence of a nonmagnetic dilution on the magnetic properties of a ZnxCd1−xCr2S4 system by means of microwave magnetic resonance

Abstract

The influence of a nonmagnetic dilution on the magnetic properties of a Zn x Cd 1−x Cr 2 S 4 system ͑0.1Ͻ x Ͻ 0.9͒ has been studied by means of microwave magnetic resonance at temperatures between 10 and 293 K. Experimental results for the peak-to-peak linewidth ⌬H pp and the slope d⌬H pp / dT have been discussed by the reduction of the exchange interaction between magnetic ions through the Zn substitution. For 0.6Ͻ x Ͻ 0.9 at T Ͻ 50 K, the electron-paramagnetic-resonance line tends toward the Lorentzian shape, indicating a medium with competing interactions with strong exchange coupling. For x Ͻ 0.4 at T Ͻ 50 K the line shapes have a rich Gaussian line indicating an increment of the interaction cluster medium.

Magnetic Spin Clusters in Ni2InVO6

“…The change of lineshape at temperature of about ∼15 K from high‐temperature Lorentzian to low‐temperature Gaussian could be attributed to the freezing of spins in random directions resulting in Gaussian lineshape. Similar effect of lineshape change from high‐temperature Lorentzian to low‐temperature Gaussian was observed in Zn x Cd 1−x Cr 2 S 4 system [9] . The Lorentzian lineshape was interpreted as the result of reduction of local interactions by the exchange interaction between magnetic ions and the Gaussian lineshape as an evidence of the dominance of local spin clusters magnetism [9] …”

“…Similar effect of lineshape change from high-temperature Lorentzian to low-temperature Gaussian was observed in Zn x Cd 1 À x Cr 2 S 4 system. [9] The Lorentzian lineshape was interpreted as the result of reduction of local interactions by the exchange interaction between magnetic ions and the Gaussian lineshape as an evidence of the dominance of local spin clusters magnetism. [9] The fitting allowed to determine the resonance field, the peak-to-peak linewidth and the amplitude of the two components of the D line.…”

“…[9] The Lorentzian lineshape was interpreted as the result of reduction of local interactions by the exchange interaction between magnetic ions and the Gaussian lineshape as an evidence of the dominance of local spin clusters magnetism. [9] The fitting allowed to determine the resonance field, the peak-to-peak linewidth and the amplitude of the two components of the D line. In Figure 6 temperature dependence of the resonance field (top panel), the linewidth (middle panel) and the integrated intensity (lower panel) of the two components labelled HF (high-field) and LF (low-field) is presented.…”

Superredes Magnéticas

“…Esta dependencia es consecuencia de la frustración de la orientación de los momentos magnéticos en la interfaz entre las capas ferro y antiferro debido a interacciones competitivas; esta dependencia ha sido observada también en el sistema la ferrita NiFe 2 O 4 48 . El producto H E por el espesor de la capa ferromagnética t FM , para todos los espesores t FM , mostrado en la figura insertada, cae sobre una única recta, indicando que el mecanismo del Exchange bias en este sistema es independiente del espesor de la capa ferromagnética.…”