DPG Phi
Verhandlungen
Verhandlungen
DPG

Dresden 2003 – scientific programme

Parts | Days | Selection | Search | Downloads | Help

MA: Magnetismus

MA 14: Poster: Schichten(1-31), Spinabh.Trsp.(32-47), Exch.Bias(48-54), Spindyn.(55-64), Mikromag.(65-76), Partikel(77-88), Oflmag.(89-92), Spinelektr.(93-98), Elektr.Theo.(99-103), Mikromag+PhasÜ+Aniso.(104-122), MagnMat.(123-134), Messm+Mol-Mag.(135-139), Kondo(140-151)

MA 14.109: Poster

Tuesday, March 25, 2003, 15:15–19:15, Zelt

Specific heat, thermal conductivity and thermoelectric power of NaFe4Sb12, KFe4Sb12 and BaFe4Sb12 — •Narayani Senthilkumaran1, Michael Baenitz1, Andreas Leithe-Jasper1, Walter Schnelle1, Annegrit Rabis1, Andrei Gippius1,2, Yuri Grin1, and Frank Steglich11MPI für Chemische Physik fester Stoffe, Nöthnitzer Str. 40, D-01187, Dresden, Germany — 2Moscow State University, Faculty of Physics, Moscow, Russia

The newly synthesized alkali metal iron antimonides with a filled skutterudite structure, NaFe4Sb12 and KFe4Sb12 together with the known BaFe4Sb12 have been investigated by means of specific heat and thermal transport measurements. Measurements of specific heat confirm ferromagnetism with a TC around 85 K for NaFe4Sb12 whereas for BaFe4Sb12 no signs of magnetic order are observed. The specific heat is analysed in terms of lattice, electronic and magnetic contributions. Furthermore relatively high values of γ (∼ 100 mJ/mol K2) are discussed in the context of high density of states N(EF), obtained from the band structure calculations. Using BaFe4Sb12 as a phonon reference, the magnetic contribution to the specific heat Cm(T) of NaFe4Sb12 has been estimated. Cm(T) shows an additional anomaly around 30 K, that could be magnetic (metamagnetic transition) or dynamic (locking-in transition of the rattlers) in origin. The thermal transport properties are compared with that of other well known compounds with filled skutterudite structure from the literature. The thermal conductivity has been analysed taking into account boundary scattering, Umklapp process, defect, electron and resonant scattering.

100% | Mobile Layout | Deutsche Version | Contact/Imprint/Privacy
DPG-Physik > DPG-Verhandlungen > 2003 > Dresden