TY - JOUR
T1 - Enhanced low-energy magnetic excitations via suppression of the itinerancy in Fe0.98-zCuzTe0.5Se0.5
AU - Wen, Jinsheng
AU - Li, Shichao
AU - Xu, Zhijun
AU - Zhang, Cheng
AU - Matsuda, M.
AU - Sobolev, O.
AU - Park, J. T.
AU - Christianson, A. D.
AU - Bourret-Courchesne, E.
AU - Li, Qiang
AU - Gu, Genda
AU - Lee, Dung Hai
AU - Tranquada, J. M.
AU - Xu, Guangyong
AU - Birgeneau, R. J.
PY - 2013/10/21
Y1 - 2013/10/21
N2 - We have performed resistivity and inelastic neutron scattering measurements on three samples of Fe0.98-zCuzTe0.5Se 0.5 with z=0, 0.02, and 0.1. It is found that with increasing Cu doping the sample's resistivity deviates progressively from that of a metal. However, in contrast to expectations that replacing Fe with Cu would suppress the magnetic correlations, the low-energy (≤12 meV) magnetic scattering is enhanced in strength, with greater spectral weight and longer dynamical spin-spin correlation lengths. Such enhancements can be a consequence of either enlarged local moments or a slowing down of the spin fluctuations. In either case, the localization of the conduction states induced by the Cu doping should play a critical role. Our results are not applicable to models that treat 3d transition metal dopants simply as effective electron donors.
AB - We have performed resistivity and inelastic neutron scattering measurements on three samples of Fe0.98-zCuzTe0.5Se 0.5 with z=0, 0.02, and 0.1. It is found that with increasing Cu doping the sample's resistivity deviates progressively from that of a metal. However, in contrast to expectations that replacing Fe with Cu would suppress the magnetic correlations, the low-energy (≤12 meV) magnetic scattering is enhanced in strength, with greater spectral weight and longer dynamical spin-spin correlation lengths. Such enhancements can be a consequence of either enlarged local moments or a slowing down of the spin fluctuations. In either case, the localization of the conduction states induced by the Cu doping should play a critical role. Our results are not applicable to models that treat 3d transition metal dopants simply as effective electron donors.
UR - http://www.scopus.com/inward/record.url?scp=84887026835&partnerID=8YFLogxK
U2 - 10.1103/PhysRevB.88.144509
DO - 10.1103/PhysRevB.88.144509
M3 - Article
AN - SCOPUS:84887026835
SN - 1098-0121
VL - 88
JO - Physical Review B - Condensed Matter and Materials Physics
JF - Physical Review B - Condensed Matter and Materials Physics
IS - 14
M1 - 144509
ER -