Abstract
We have developed an underscreened Kondo lattice model with an intra-site Kondo exchange interaction JK between the conduction band and localized 5f electrons-described by S = 1 spins in the f2 configuration-and an inter-site ferromagnetic exchange f-f interaction JH. Using a fermionic representation for the spin operators and a mean-field approximation we obtain, from T = 0 up to a critical temperature, a Kondo-ferromagnetic coexistence. This is in agreement with the experimental situation of some Uranium compounds, such as UTe or UCu0.9 Sb2, which order ferromagnetically with a Curie temperature of order 100 K and present also a Kondo behavior. The Curie and Kondo temperatures are also determined.
Original language | English (US) |
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Pages (from-to) | 428-430 |
Number of pages | 3 |
Journal | Journal of Magnetism and Magnetic Materials |
Volume | 310 |
Issue number | 2 SUPPL. PART 1 |
DOIs | |
State | Published - Mar 2007 |
Bibliographical note
Funding Information:This work was partially supported by Brazilian agencies CNPq and FAPERGS through PRONEX 04/0874.9. JRI thanks the hospitality of LPS, Orsay, France, and MPIPKS, Dresden, Germany, and NBP thanks FAPERGS for support during her stay at IF-UFRGS, Porto Alegre, Brazil.
Keywords
- Kondo lattice
- Underscreened Kondo model
- Uranium compounds