The influence of substitution of Mn by Fe and Co on magnetocaloric effect and magnetoresistance properties of SmMn 2Ge 2

DİNÇER İ., Elerman Y.

Journal of Magnetism and Magnetic Materials, cilt.326, ss.50-57, 2013 (SCI-Expanded) identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 326
  • Basım Tarihi: 2013
  • Doi Numarası: 10.1016/j.jmmm.2012.08.007
  • Dergi Adı: Journal of Magnetism and Magnetic Materials
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.50-57
  • Anahtar Kelimeler: Magnetic phase transition, Magnetocaloric effect, Magnetoresistance
  • Ankara Üniversitesi Adresli: Evet

Özet

Magnetocaloric and magnetoresistance properties of SmMn 2-xFe xGe 2 (x=0.05 and 0.10) and SmMn 2-xCo xGe 2 (x=0.05 and 0.15) compounds have been studied by magnetic and resistance measurements in the temperature range between 30 and 350 K. All compounds exhibit metamagnetic transition from antiferromagnetism to ferromagnetism around the Sm moments ferromagnetic ordering temperature-T Sm and Mn moments antiferromagnetic ordering temperature-T N1. The magnetic entropy changes of these compounds are estimated from the Maxwell equation, Maxwell Clausius Clapeyron equation, Landau theory and mean-field theory. The maximum magnetic entropy change values of SmMn 1.90Fe 0.10Ge 2 and SmMn 1.85Co 0.15Ge 2 compounds are -8.1 J kg -1 K -1 and -5.1 J kg -1 K -1 in a magnetic field change of 5 T, respectively. These compounds show negative magnetoresistance around the magnetic phase transition temperatures. The magnetoresistance value of SmMn 1.95Fe 0.05Ge 2 is -23 at T Sm which is bigger than the magnetoresistance value of SmMn 2Ge 2 (-15). © 2012 Elsevier B.V.