Mossbauer spectroscopy evidence for the lack of iron magnetic moment in superconducting FeSe

JOURNAL OF ALLOYS AND COMPOUNDS

卷:494

Article

Blachowski, A.¹  Ruebenbauer, K.¹  Zukrowski, J.²  Przewoznik, J.²  Wojciechowski, K.³  Stadnik, Z. M.⁴ 

[1] Pedag Univ, Inst Phys, Mossbauer Spect Div, PL-30084 Krakow, Poland

[2] AGH Univ Sci & Technol, Dept Solid State Phys, Fac Phys & Appl Comp Sci, PL-30059 Krakow, Poland

[3] AGH Univ Sci & Technol, Dept Inorgan Chem, Fac Mat Sci & Ceram, PL-30059 Krakow, Poland

[4] Univ Ottawa, Dept Phys, Ottawa, ON K1N 6N5, Canada

关键词: Iron-based superconductor;    Mossbauer spectroscopy;   

DOI  :  10.1016/j.jallcom.2009.12.095

来源: Elsevier

【 摘 要 】

Superconducting FeSe has been investigated by measurements of the magnetic susceptibility versus temperature and Mossbauer spectroscopy at various temperatures including strong external magnetic fields applied to the absorber. It was found that isomer shift exhibits sharply defined increase at about 105K leading to the lowering of the electron density on iron nucleus by 0.02 electron a.u.(-3). Above jump in the electron density is correlated with the transition from the P4/nmm to the Cmma structure, while decreasing temperature. Mossbauer measurements in the external magnetic field and for temperatures below transition to the superconducting state revealed null magnetic moment on iron atoms. Hence, the compound exhibits either Pauli paramagnetism or diamagnetic behavior. The principal component of the electric field gradient on the iron nucleus was found as negative on the iron site. (C) 2009 Elsevier B.V. All rights reserved.

【 授权许可】

Free