Are there crystal field levels in UPd2Al3? We answer, THERE ARE
Abstract
Description
We claim that crystal field (CEF) levels exist in UPd2Al3 in contrary to a recent claim of Hiess et al. (cond-mat/0411041) and Bernhoeft et al. (cond-mat/0411042), that there is no experimental evidence for discrete crystal field levels in this superconducting heavy-fermion antiferromagnet. We claim that excitations revealed by Krimmel et al. (J. Phys.: Condens. Matter 8 (1996) 1677 in inelastic-neutron-scattering (INS) studies are i) crystal-field excitations described by us within ii) the 5f3 (U3+) configuration. Moreover, our 5f3 (U3+) scheme, presented in Physica B 276-278 (2000) 803 and in Czech. J. Phys. 54 (2004) D295, provides a clear physical explanation for the 1.7 meV excitation (magnetic exciton) as associated to the removal of the Kramers-doublet ground state degeneracy in the antiferromagnetic state. The crystal-field theory completed by strong intra-atomic correlations and intersite spin-dependent interactions to the Quantum Atomistic Solid State Theory (QUASST), offers the meV energy scale needed for description of magnetic and electronic properties of compounds containing open-shell 3d, 4f, 5f atoms. The derived set of CEF parameters for the U3+ state reproduces both the INS excitations, temperature dependence of the heat capacity, large uranium magnetic moment as well as its direction.
PACS: 71.70.E, 75.10.D
Keywords: Crystalline Electric Field, Heavy fermion, magnetism, UPd2Al3
10 pages in RevTex4, 2 figures, in version 2 only title is changed from: Are, or not, CEF levels? We answer, ARE
10 pages in RevTex4, 2 figures, in version 2 only title is changed from: Are, or not, CEF levels? We answer, ARE