Dilute magnetism and vibrational entropy inFe2Al5 Academic Article uri icon

abstract

  • Fe2 Al5 contains a Fe-Al matrix through which are threaded disordered one-dimensional chains of overlapping Al sites. We report magnetic, nuclear-magnetic-resonance (NMR), and specific-heat measurements addressing its magnetic and vibrational properties. The Curie-type susceptibility is found to be due to dilute moments, likely due to wrong-site Fe atoms. A 27 l NMR shift and spin-lattice relaxation measurements confirm these to be indirectly coupled through a Ruderman-Kittel-Kasuya-Yoshida-type interaction. Specific-heat results indicate a large density of low-energy vibrational modes. These excitations generate a linear- T contribution to the specific heat, which however freezes out below about 10 K. These results are attributed to the presence of anharmonic vibrational modes associated with the disordered structural chains. 2010 The American Physical Society.

published proceedings

  • Physical Review B

author list (cited authors)

  • Chi, J. i., Zheng, X., Rodriguez, S. Y., Li, Y., Gou, W., Goruganti, V., Rathnayaka, K., & Ross, J. H

publication date

  • January 1, 2010 11:11 AM