TY - JOUR
T1 - Spin excitations in iron oxypnictide superconductor system
AU - Shamoto, Shin Ichi
AU - Ishikado, Motoyuki
AU - Wakimoto, Shuichi
AU - Kodama, Katsuaki
AU - Kajimoto, Ryoichi
AU - Arai, Masatoshi
AU - Fukuda, Tatsuo
AU - Nakamura, Hiroki
AU - Machida, Masahiko
AU - Eisaki, Hiroshi
N1 - Funding Information:
This work was supported by Grant-in-Aids for Specially Promoted Research (17001001) from the Ministry of Education, Culture, Sports, Science and Technology of Japan (MEXT) and JST, Transformative Research-Project on Iron Pnictides (TRIP). Inelastic neutron scattering experiment was partially conducted under UK-Japan collaboration.
PY - 2010/12
Y1 - 2010/12
N2 - The spin excitations in the LaFeAsO 1-xF x system have been studied by inelastic neutron scattering measurements with powder samples. In the parent compound, the spin excitation was observed as a magnetic rod at (π, π, l) in the downfolded tetragonal Brillouin zone. It persisted even in the tetragonal phase at T = 280 K. In the superconducting compounds with x = 0.057 and 0.082, the spin excitations developed below the superconducting transition temperatures up to the same order of magnitude as that in the parent compound, and they were peaked at about 11 meV. The spin excitation, however, almost disappeared in an overdoped compound with x = 0.158, which exhibited only low temperature superconductivity below 7 K. These results indicate that the present superconductivity intimately correlates with the spin fluctuation possibly in relation to the nesting condition between the Fermi surfaces at Γ and M points.
AB - The spin excitations in the LaFeAsO 1-xF x system have been studied by inelastic neutron scattering measurements with powder samples. In the parent compound, the spin excitation was observed as a magnetic rod at (π, π, l) in the downfolded tetragonal Brillouin zone. It persisted even in the tetragonal phase at T = 280 K. In the superconducting compounds with x = 0.057 and 0.082, the spin excitations developed below the superconducting transition temperatures up to the same order of magnitude as that in the parent compound, and they were peaked at about 11 meV. The spin excitation, however, almost disappeared in an overdoped compound with x = 0.158, which exhibited only low temperature superconductivity below 7 K. These results indicate that the present superconductivity intimately correlates with the spin fluctuation possibly in relation to the nesting condition between the Fermi surfaces at Γ and M points.
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U2 - 10.1016/j.physc.2009.11.132
DO - 10.1016/j.physc.2009.11.132
M3 - Article
AN - SCOPUS:78649711921
VL - 470
SP - S284-S287
JO - Physica C: Superconductivity and its Applications
JF - Physica C: Superconductivity and its Applications
SN - 0921-4534
IS - SUPPL.1
ER -