EFFECTS OF ELECTRON CORRELATION ON MAGNETIC COMPTON PROFILES OF NI IN THE GW APPROXIMATION

 

Yasunori Kubo

 

Department of Physics, College of Humanities and Sciences, Nihon University, Tokyo 156-8550 ( kubo@chs.nihon-u.ac.jp)

 

 

The magnetic Compton profiles (MCPÕs) are studied with the conventional band theory based on the local-density approximation(LDA) and so-called GW approximation (GWA) connected band theory. In the GWA, the basis sets, eigen-energies and eigen-states generated by the full-potential linearized augmented-plane wave method(FLAPW), are used.

Since the magnetic moment of Ni is 0.6 mB , which is about 4 times smaller than that of Fe, it is not easy to measure MCP with good statistical accuracy. However, recent MCPÕs [1,2] using Storage-Ring have demonstrated discrepancies between the experiments and conventional band calculations using LDA in lower momentum region, where the Fermi surface structures and the hybridization between the 3d- and s,p- electrons predominantly influence the momentum distributions of magnetic electrons. The discrepancies are examined from the point of view of electron correlation effects. The occupation number densities N(k)Õs are evaluated from a first-principle calculation of the spectral function within the GWA. The MCPÕs are calculated using the N(k)Õs.

 

References

1           Dixon, M.A.G., Duffy, J.A., Gardelis, S., McCarthy, J.E., Cooper, M.J., Dugdale, S.B., Jarlborg, T., Timms, D.N., (1998) J. Phys.: Condens. Matter 10 2759-2771.

2           Kakutani, Y., Kubo, Y., Koizumi, A., Sakai, N., Ahuja, B.L., Sharma, B.K. (2003) J. Phys. Soc. Jpn. 72 in print.