An inelastic neutron scattering study of the Kondo semiconductor CeNiSn in high magnetic field

• Published in: Journal of physics. Condensed matter 1997-02, Vol.9 (7), p.1599-1608, Article 1599
• Main Authors: Raymond, S, Regnault, L P, Sato, T, Kadowaki, H, Pyka, N, Nakamoto, G, Takabatake, T, Fujii, H, Isikawa, Y, Lapertot, G, Flouquet, J
• Format: Article
• Language: English
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Exact sciences and technology; Magnetic properties and materials; Magnetically ordered materials: other intrinsic properties; Physics; Spin arrangements in magnetically ordered materials (including neutron and spin-polarized electron studies, synchrotron-source x-ray scattering, etc.); Valence fluctuation, kondo lattice, and heavy-fermion phenomena
• ISSN: 0953-8984; 1361-648X
• DOI: 10.1088/0953-8984/9/7/021

We have used inelastic neutron scattering to determine the spin dynamics in the Kondo insulator CeNiSn under magnetic fields up to 10 T applied parallel to the easy a axis. The well known excitations peaked at h omega =2 meV located at the Brillouin zone centre and at h omega =4 meV located at the Brillouin zone border were studied comparatively. At the scattering vectors (010) and (001) the peak shifts continuously from 2 to 2.5 meV with the field. No Zeeman splitting could be detected at the accuracy of our measurements. For the 4 meV excitation studied at the scattering vector (00.51), a field as large as 10 T begins to fill in the gap whereas there is no appreciable change in the spin dynamics between 0 and 6 T. The main feature is the broadening of the response. Experimental results are compared to recent theoretical developments.