ntroduction to the NMTO method: Direct generation of Wannier functions and its applications

Date & Time
25 October 2005 (Tue), 10:30 am - 12:00 am
Place
6F seminar room, Sengen site
Speaker
Dr. Atsushi Yamasaki (山崎敦嗣博士)
Affiliation
Max-Planck-Institut fuer Festkperforschung, Stuttgart
Title
ntroduction to the NMTO method: Direct generation of Wannier functions and its applications
Abstract
Recently new generation of the LMTO method is developing, so-called NMTO, Nth-order muffin-tin orbital. The keywords, which is nearly connected with each other, are as follows: (1)minimal basis set (by massive downfolding) (2)short-ranged orbitals (by screening transformations) (3)accurate and robust (by overlapping MT-potentials and a polynomial approximation to the energy dependence of the partial-wave set) Those are explained briefly. With the massive downfolding and energy-selective partial waves, it is possible to generate Wannier functions directly, instead of via projection from the delocalized Bloch states. NMTO Wannier functions can be used to visualize chemical bonding and to construct effective (Hubbard-type) Hamiltonians, which are including chemical trends and material dependencies correctly, for strongly correlated systems. The results of the series of 3d(t$_{2g}$)$^1$ perovskites by means of LDA+DMFT are presented. If time permits, other results are also given. These MTO's have significant advantages over those used in the past.
Contact
Dr. Igor Solovyev