Zobrazeno 1 - 10
of 216
pro vyhledávání: '"Mambrini, M."'
Publikováno v:
Phys. Rev. B 84, 024406 (2011)
We present a comprehensive computational study of the phase diagram of the frustrated S=1/2 Heisenberg antiferromagnet on the honeycomb lattice, with second-nearest (J2) and third-neighbor (J3) couplings. Using a combination of exact diagonalizations
Externí odkaz:
http://arxiv.org/abs/1102.5325
Publikováno v:
Modern Physics Letters B, Volume: 25, Issues: 12-13(2011) pp. 917-928
In order to quantify entanglement between two parts of a quantum system, one of the most used estimator is the Von Neumann entropy. Unfortunately, computing this quantity for large interacting quantum spin systems remains an open issue. Faced with th
Externí odkaz:
http://arxiv.org/abs/1011.6530
Publikováno v:
Phys. Rev. B 80, 184427 (2009)
Aiming to describe frustrated quantum magnets with non-magnetic singlet ground states, we have extended the Rokhsar-Kivelson (RK) loop-expansion to derive a generalized Quantum Dimer Model containing only connected terms up to arbitrary order. For th
Externí odkaz:
http://arxiv.org/abs/0905.2039
We investigate the properties of the two-dimensional frustrated quantum antiferromagnet on the square lattice, especially at infinitesimal doping. We find that next nearest neighbor (N.N.) J2 and next-next N.N. J3 interactions together destroy the an
Externí odkaz:
http://arxiv.org/abs/cond-mat/0606780
Publikováno v:
Phys. Rev. B 74, 144422 (2006)
Using both exact diagonalizations and diagonalizations in a subset of short-range valence bond singlets, we address the nature of the groundstate of the Heisenberg spin-1/2 antiferromagnet on the square lattice with competing next-nearest and next-ne
Externí odkaz:
http://arxiv.org/abs/cond-mat/0606776
Publikováno v:
Phys. Rev. B 68, 224416 (2003).
We consider the effects of doping the S = 1/2 kagome lattice with static impurities. We demonstrate that impurities lower the number of low-lying singlet states, induce dimer-dimer correlations of considerable spatial extent, and do not generate free
Externí odkaz:
http://arxiv.org/abs/cond-mat/0306299
Publikováno v:
Eur. Phys. J. B 26, 167-183 (2002)
In the first part of this paper, the extension of the Lieb-Schultz-Mattis theorem to dimensions larger than one is discussed. A counter example to the original formulation of Lieb-Schultz-Mattis and Affleck is exhibited and a more precise statement i
Externí odkaz:
http://arxiv.org/abs/cond-mat/0112360
Exact diagonalizations of the spin-1/2 Heisenberg model on the checkerboard lattice have been performed for sizes up to N=36 in the full Hilbert space and N=40 in the restricted subspace of first neighbor dimers. This antiferromagnet does not break S
Externí odkaz:
http://arxiv.org/abs/cond-mat/0108070
Li$_2$VO(Si,Ge)O$_4$, a prototype of a two-dimensional frustrated quantum Heisenberg antiferromagnet
Publikováno v:
Phys. Rev. Lett. 85, 1318 (2000)
NMR and magnetization measurements in Li$_2$VOSiO$_4$ and Li$_2$VOGeO$_4$ are reported. The analysis of the susceptibility shows that both compounds are two-dimensional $S=1/2$ Heisenberg antiferromagnets on a square lattice with a sizeable frustrati
Externí odkaz:
http://arxiv.org/abs/cond-mat/0005273
Autor:
Mambrini, M., Mila, F.
{Extensive calculations in the short-range RVB (Resonating valence bond) subspace on both the trimerized and the regular (non-trimerized) Heisenberg model on the kagome lattice show that short-range dimer singlets capture the specific low-energy feat
Externí odkaz:
http://arxiv.org/abs/cond-mat/0003080