TY - JOUR
T1 - Observation of lattice softening at Tc in the FeSe0.5Te0.5 superconductor
AU - Lindén, J.
AU - Libäck, J. P.
AU - Karppinen, M.
AU - Rautama, E. L.
AU - Yamauchi, H.
PY - 2011/1
Y1 - 2011/1
N2 - Polycrystalline samples of FeSe0.5Te0.5 were synthesized using a conventional solid-state reaction method. The onset of bulk superconductivity transition was confirmed by SQUID magnetometry at 12.5 K. 57Fe Mssbauer spectra in transmission geometry were recorded at temperatures between 6.0 and 320 K. Both the isomer shift and the total absorption started to drop about Tc, indicating a softening of the lattice. The drop is estimated to correspond to at least 60 K from the original Debye temperature θD≈460 K. Seebeck measurements indicate that the samples are n-type conductors at low temperatures with a cross-over to p-type conductivity around 135 K. The zero Seebeck coefficient is seen below 10.6 K.
AB - Polycrystalline samples of FeSe0.5Te0.5 were synthesized using a conventional solid-state reaction method. The onset of bulk superconductivity transition was confirmed by SQUID magnetometry at 12.5 K. 57Fe Mssbauer spectra in transmission geometry were recorded at temperatures between 6.0 and 320 K. Both the isomer shift and the total absorption started to drop about Tc, indicating a softening of the lattice. The drop is estimated to correspond to at least 60 K from the original Debye temperature θD≈460 K. Seebeck measurements indicate that the samples are n-type conductors at low temperatures with a cross-over to p-type conductivity around 135 K. The zero Seebeck coefficient is seen below 10.6 K.
KW - A. Pnictide superconductors
KW - D. Lattice softening
KW - E. Fe Mssbauer spectroscopy
KW - E. Hyperfine interactions
UR - http://www.scopus.com/inward/record.url?scp=78650510466&partnerID=8YFLogxK
U2 - 10.1016/j.ssc.2010.11.006
DO - 10.1016/j.ssc.2010.11.006
M3 - Article
AN - SCOPUS:78650510466
SN - 0038-1098
VL - 151
SP - 130
EP - 134
JO - Solid State Communications
JF - Solid State Communications
IS - 2
ER -