Ground-state ferromagnetism in a doubly orbitally degenerate model

نویسندگان
چکیده

برای دانلود باید عضویت طلایی داشته باشید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

The ground state phases of orbitally degenerate spinel oxides

I review the microscopic spin-orbital Hamiltonian and ground state properties of spin one-half spinel oxides with threefold t2g orbital degeneracy. It is shown that for any orbital configuration a ground state of corresponding spin only Hamiltonian is infinitely degenerate in the classical limit. The extensive classical degeneracy is lifted by the quantum nature of the spins, an effect similar ...

متن کامل

Interplay of Mott transition and ferromagnetism in the orbitally degenerate Hubbard model

A slave-boson representation for the degenerate Hubbard model is introduced. The location of the metalto-insulator transition that occurs at commensurate densities is shown to depend weakly on the band degeneracy M . The relative weights of the Hubbard subbands depend strongly on M , as well as the magnetic properties. It is also shown that a sizable Hund’s rule coupling is required in order to...

متن کامل

A Potts model with infinitely degenerate ground state

A q-component Potts model with ferromagnetic and antiferromagnetic interactions in the two respective directions of a square lattice is considered. An argument is given showing that an ordered phase can exist in this model, even though the ground state is disordered and infinitely degenerate. We use the Migdal-Kadanoff transformation to obtain a closed-form expression for its critical point. We...

متن کامل

Ferromagnetism in the Hubbard Model { Examples from Models with Degenerate Single-electron Ground States

Whether spin-independent Coulomb interaction can be the origin of a realistic ferromag-netism in an itinerant electron system has been an open problem for a long time. Here we study a class of Hubbard models on decorated lattices, which have a special property that the corresponding single-electron Schrr odinger equation has N d-fold degenerate ground states. The degeneracy N d is proportional ...

متن کامل

Orbitally degenerate spin-fluctuation model for heavy-fermion superconductivity.

Manuscript is plain TeX with macros. Figures start at FIGURES BEGIN HERE, with instructions on what to do to get them. In this paper, a generalization of standard spin fluctuation theory is considered by replacing the simple Hubbard interaction by the screened Hartree-Fock interaction for f electrons. This model is then used in both an LS and a JJ coupling scheme to construct the particle-parti...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

ژورنال

عنوان ژورنال: Physical Review B

سال: 2001

ISSN: 0163-1829,1095-3795

DOI: 10.1103/physrevb.64.144428