Comment on "quantum phase transition of the randomly diluted Heisenberg antiferromagnet on a square lattice".
Abstrak
In Phys. Rev. Lett. 84, 4204 (2000) (cond-mat/9905379), Kato et al. presented quantum Monte Carlo results indicating that the critical concentration of random non-magnetic sites in the two-dimensional antiferromagnetic Heisenberg model equals the classical percolation density; pc=0.407254. The data also suggested a surprising dependence of the critical exponents on the spin S of the magnetic sites, with a gradual approach to the classical percolation exponents as S goes to infinity. I here argue that the exponents in fact are S-independent and equal to those of classical percolation. The apparent S-dependent behavior found by Kato et al. is due to temperature effects in the simulations as well as a quantum effect that masks the true asymptotic scaling behavior for small lattices.
Penulis (1)
A. Sandvik
Akses Cepat
- Tahun Terbit
- 2000
- Bahasa
- en
- Total Sitasi
- 12×
- Sumber Database
- Semantic Scholar
- DOI
- 10.1103/PhysRevLett.86.3209
- Akses
- Open Access ✓