Polaronic Aspects and Phase Diagram of the 2D Ferromagnetic Kondo Model
Abstract
The 2D ferromagnetic Kondo model with classical corespins is studied via unbiased MC simulations. A canonical algorithm for finite temperatures is developed. We show that with realistic parameters for the manganites and at low temperatures, the model does not show phase separation on a 2D lattice but, rather stabilizes individual ferromagnetic polarons. Within the ferromagnetic polaron picture, the pseudogap in the one-particle DOS can easily be explained. Further, we explore the influence of the AFM superexchange coupling J'. We find that larger J' stabilizes the polarons and leads to the ''flux phase'' around half filling of the lower Kondo band. We also find that lower temperatures further enhance polaronic behavior at realistic parameters J' > 0.01. Detailed phase diagrams for β=50 and β=80 are determined, in which a narrow window in parameter space exists for phase separation.
- Publication:
-
APS March Meeting Abstracts
- Pub Date:
- March 2004
- Bibcode:
- 2004APS..MAR.C1104D