Europhys. Lett.
Volume 74, Number 1, April 2006
Page(s) 124 - 130
Section Condensed matter: electronic structure, electrical, magnetic, and optical properties
Published online 24 February 2006
Europhys. Lett., 74 (1), pp. 124-130 (2006)
DOI: 10.1209/epl/i2005-10504-5

Calculated de Haas-van Alphen frequencies of $\chem{NpCoGa_5}$

I. Opahle1, S. Elgazzar1, 2, V. D. P. Servedio3, 4, Manuel Richter1 and P. M. Oppeneer5

1  IFW Dresden - P.O. Box 270116, D-01171 Dresden, Germany
2  Department of Physics, Faculty of Science, Menoufia University Shebin El-kom, Egypt
3  Centro Studi e Ricerche E. Fermi - Compendio Viminale, Roma, Italy
4  Dipartimento di Informatica e Sistemistica, Università di Roma "La Sapienza" Via Salaria 113, 00198 Roma, Italy
5  Department of Physics, Uppsala University - Box 530, S-751 21 Uppsala, Sweden

received 13 December 2005; accepted in final form 6 February 2006
published online 24 February 2006

The electronic structure and magnetic properties of $\chem{NpCoGa_5}$ are investigated in the framework of relativistic density functional theory in the local spin density approximation (LSDA) with and without orbital polarization (OP) corrections. A detailed analysis of the Fermi surface is presented. Comparison of the calculated angular dependence of the de Haas-van Alphen frequencies with recent experimental data shows that LSDA reproduces the main features of the Fermi surface topology, while the spin and orbital moments of $\chem{NpCoGa_5}$ are less well described. The inclusion of OP corrections leads to a very good agreement between calculated and measured de Haas-van Alphen frequencies, but does not yield a significant improvement of the calculated magnetic properties. We predict that $\chem{NpCoGa_5}$ shows an intrinsic GMR effect at moderate magnetic field.

71.18.+y - Fermi surface: calculations and measurements; effective mass, g factor.
71.15.Rf - Relativistic effects.
71.20.-b - Electron density of states and band structure of crystalline solids.

© EDP Sciences 2006