Physics – Condensed Matter
Scientific paper
1996-09-24
Phys. Rev. B 55, 4149 (1997)
Physics
Condensed Matter
10 pages, REVTeX, 14 figures included using psfig.sty
Scientific paper
10.1103/PhysRevB.55.4149
The two dimensional Hubbard model in the presence of diagonal and off-diagonal disorder is studied at half filling with a finite temperature quantum Monte Carlo method. Magnetic correlations as well as the electronic compressibility are calculated to determine the behavior of local magnetic moments, the stability of antiferromagnetic long range order (AFLRO), and properties of the disordered phase. The existence of random potentials (diagonal or ``site'' disorder) leads to a suppression of local magnetic moments which eventually destroys AFLRO. Randomness in the hopping elements (off-diagonal disorder), on the other hand, does not significantly reduce the density of local magnetic moments. For this type of disorder, at half-filling, there is no ``sign-problem'' in the simulations as long as the hopping is restricted between neighbor sites on a bipartite lattice. This allows the study of sufficiently large lattices and low temperatures to perform a finite-size scaling analysis. For off-diagonal disorder AFLRO is eventually destroyed when the fluctuations of antiferromagnetic exchange couplings exceed a critical value. The disordered phase close to the transition appears to be incompressible and shows an increase of the uniform susceptibility at low temperatures.
Scalettar Richard T.
Ulmke Martin
No associations
LandOfFree
Magnetic Correlations in the Two Dimensional Anderson-Hubbard Model does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Magnetic Correlations in the Two Dimensional Anderson-Hubbard Model, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Magnetic Correlations in the Two Dimensional Anderson-Hubbard Model will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-695537