Magnetic properties and the inverse magnetocaloric effect in Mn3Ga1-xPtxC and Mn3Ga(C,N) at the magnetostructural transition


Çakır Ö. , Acet M.

joint European Magnetic Symposia , Parma, Italy, 9 - 14 September 2012, pp.463

  • Publication Type: Conference Paper / Summary Text
  • City: Parma
  • Country: Italy
  • Page Numbers: pp.463

Abstract

Magnetic properties and the inverse magnetocaloric effect in Mn3Ga1-xPtxC at the magnetostructural transitionÖ. Cakir1, M. Acet 2(1) Physics department, Yildiz Technical University, 34210 Istanbul,Turkey, (2) Physics Dept., Duisburg Essen University, 47048 Duisburg, GermanyThe ferromagnetic to antiferromagnetic transition on decreasing temperature in the antiperovskite Mn3Ga1-xPtxC is accompanied by a structural distortion which leads to thermal hysteresis. This magnetostructural transition occurs in the temperature range 150 T 170 K and has a thermal hysteresis-width of about 4-10 K as observed from magnetization measurements. The transition shifts to lower temperature under higher applied fi elds. This shift is accompanied by a fi eld-induced reverse transformation from the antiferromagnetic to the ferromagnetic state, giving rise to the inverse magnetocaloric effect. We study the inverse magnetocaloric effect, both by determining the entropy change from magnetization isotherms and by direct adiabatic temperature-change measurement around the transition. We further study the properties of the effect of the thermal hysteresis on the inverse magnetocaloric effect.