Magnetism induced by interlayer electrons in the quasi-two-dimensional electride Y
C; Inelastic neutron scattering study
擬2次元エレクトライドY
Cにおける層間電子由来磁性
玉造 博夢
; 村上 洋一*; 倉本 義夫*; 佐賀山 基*; 松浦 直人*; 川北 至信
; 松石 聡*; 鷲尾 康仁*; 井下 猛*; 浜田 典昭*; 細野 秀雄*
Tamatsukuri, Hiromu; Murakami, Yoichi*; Kuramoto, Yoshio*; Sagayama, Hajime*; Matsuura, Masato*; Kawakita, Yukinobu; Matsuishi, Satoru*; Washio, Yasuhito*; Inoshita, Takeshi*; Hamada, Noriaki*; Hosono, Hideo*
Magnetic excitations in layered electride Y
C have been found by inelastic neutron scattering. We have observed weak but clear magnetic scattering around the wave number
, but no magnetic order down to the lowest temperature measured (7 K). The imaginary part of the dynamical susceptibility deduced is well described by the Lorentz function of energy
for each momentum
. The width
of the Lorentzian is proportional to
with
at
K. We have also found that with increasing
the magnetic form factor decays faster than that of a
electron in a single Y atom, which indicates a more extended magnetic moment in Y
C. These results provide experimental evidence that the itinerant magnetism in Y
C originates from the anionic electrons that reside in the interlayers. The Curie-Weiss-like behavior of the magnetic susceptibility reported in Y
C is ascribed to the mode coupling effects of spin fluctuations.