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Spin Fluctuations and Non-Fermi-Liquid Behavior of CeNi_2Ge_2

H. Kadowaki·B. Fåk·T. Fukuhara·K. Maezawa·K. Nakajima·M. A. Adams·S. Raymond·J. Flouquet
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Abstract

Neutron scattering shows that non-Fermi-liquid behavior of the heavy-fermion compound CeNi_2Ge_2 is brought about by the development of low-energy spin fluctuations with an energy scale of 0.6 meV. They appear around the antiferromagnetic wave vectors $({1/2} {1/2} 0)$ and $(0 0 {3/4})$ at low temperatures, and coexist with high-energy spin fluctuations with an energy scale of 4 meV and a modulation vector $(0.23, 0.23, {1/2})$. This unusual energy dependent structure of $\text{Im} χ(\bm{Q}, E)$ in $\bm{Q}$ space suggests that quasiparticle bands are important.

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H. Kadowaki, B. Fåk, T. Fukuhara, K. Maezawa, K. Nakajima, M. A. Adams, S. Raymond, J. Flouquet. 2003-09-23. Spin Fluctuations and Non-Fermi-Liquid Behavior of CeNi_2Ge_2. https://doi.org/10.1103/physrevb.68.140402

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