Inelastic neutron scattering studies of doped CeNiSn and CeRhSb : Crystal-field excitations and origin of the pseudogap

So J.-Y.

Oh Seung June

Park Junghwan Gahb

Adroja D. T.

McEwen Keith A.

Takabatake Toshiro

Physical Review B - Condensed Matter and Materials Physics

The formation of pseudogaps in CeNiSn and CeRhSb has been a puzzle for more than a decade. In order to uncover the mystery, we have undertaken inelastic neutron scattering studies of CeNi0.85Cu0.15Sn and CeRh1-xPdxSb with x=0.1 and 0.2. From this study, we have succeeded in finding two observable crystal field excitations experimentally. Our subsequent analysis using a crystalline electric field (CEF) Hamiltonian reveals that the experimental observation can be explained by two separate solutions of the CEF Hamiltonian with different ground state wave functions. Interestingly enough, these two solutions are the same ones favored by two independent theoretical models. We have made further analysis and calculations using a superposition model in order to distinguish between these two solutions and, furthermore, discuss our findings with respect to the currently available theories. Our new results shed light on the nature of the gap formation of CeNiSn and CeRhSb.

eng

American Physical Society

Copyright (c) 2005 The American Physical Society.

[ISSN] 1098-0121

[DOI] 10.1103/PhysRevB.71.214441

[NCID] AA11187113

[DOI] http://dx.doi.org/10.1063/1.1568819