Related papers: Doped dimerized spin chains: Another path to super…
In the presence of nonlocal phase shift effects, a quasiparticle can remain topologically stable even in a spin-charge separation state due to the confinement effect introduced by the phase shifts at finite doping. True deconfinement only…
This paper has been withdrawn by the authors. Some of the arguments developed in the paper are erroneous. They will be rectified in a later publication.
This paper has been withdrawn by the author because similar published work on the topic was overlooked. See S. Deser and A. Waldron, Nucl. Phys. B 631, 369-387 (2002).
We study the effects of hole doping on one-dimensional Mott insulators with orbital degrees of freedom. We describe the system in terms of a generalized t-J model. At a specific point in parameter space the model becomes integrable in…
By systematic chemical substitution of Pt and Ni in the newly-discovered superconductor Nb$_2$PdS$_5$ ($T_c\sim$6 K), we study the evolution of its superconducting properties with doping, focussing on the behavior of the upper critical…
We present a theory for the lightly doped t-J model which is of possible relevance for the normal state of underdoped cuprates. Starting from an arbitrary dimer covering of the plane an exact representation of the t-J Hamiltonian in terms…
This paper has been withdrawn
Based on a variational approach, we propose that there are two kinds of low energy states in the t-J type models at low doping. In a quasi-particle state an unpaired spin bound to a hole with a well-defined momentum can be excited with spin…
This paper has been withdrawn since it contains some discrepancy with othe authers's recent result. We will not post this until this discrepancy is resolved.
Superconductivity in doped quantum paramagnets has been a subject of long theoretical inquiry. In this work we report a density matrix renormalization group study of lightly doped $t$-$J$ models on the square lattice (doped hole densities…
This paper has been withdrawn by the author.
This paper has been withdrawn by the author. A revised and expanded version is gr-qc/9907028 (Phys.Rev. D60 (1999) 104043).
This paper has been withdrawn by the authors.
This paper was withdrawn by the authors.
We show that several features (the three-dimensional XY universality for moderate underdoping, the almost-BCS behaviour for moderate overdoping and the critical exponent) of the superfluid density in hole-doped cuprates hint at a composite…
This paper is withdrawn due to copyright restrictions. The final version will become available at this url: http://pubs.acs.org/journals/jpcbfh/
This paper has been withdrawn by the author due to a crucial sign error in equation 1
We study the renormalization of the staggered magnetization of a two-dimensional antiferromagnet as a function of hole doping, in the framework of the t-J model. It is shown that the motion of holes generates decay of spin waves into…
We study the quantum transition from an antiferromagnet to a superconductor in a model for electron- and hole-doped cuprates by means of a variational cluster perturbation theory approach. In both cases, our results suggest a tendency…
This paper has been withdrawn by the author(s), as required by JPC-Journal of Physical Chemistry for reasons of publication.