Abstract
In the limit of weak exchange J at low hole concentration (formula presented) the ground state of the two-dimensional (formula presented) model is believed to be ferromagnetic. We study the leading instability of this Nagaoka state, which emerges with increasing J. Both exact diagonalization of small clusters, and a semiclassical analytical calculation of larger systems show that above a certain critical value of the exchange, (formula presented) Nagaoka’s state is unstable to phase separation. In a finite-size system a bubble of antiferromagnetic Mott insulator appears in the ground state above this threshold. The size of this bubble depends on (formula presented) and scales as a power of the system size N.
Original language | English (US) |
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Pages (from-to) | 1-7 |
Number of pages | 7 |
Journal | Physical Review B - Condensed Matter and Materials Physics |
Volume | 65 |
Issue number | 13 |
DOIs | |
State | Published - 2002 |
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics