We reconsider some of the previous studies of the interactions between the holes and the spin background in the Hubbard model in the small-doping limit. We show that the hole-hole interaction due to the transverse magnetization fluctuations (i.e., spin waves) is finite at arbitrarily small hole density. It may be comparable to the coupling due to the longitudinal magnetization fluctuations (which are the essence of the ``spin-bag'' mechanism of Schrieffer, Wen, and Zhang). This suggests that the two couplings should be considered simultaneously when studying the phase diagram of the lightly doped quantum antiferromagnets at the values of U/t relevant to the high- ${\mathit{T}}_{\mathit{c}}$ superconducting materials. We also show that in the large-(U/t) limit the Hubbard-model expressions for the coupling of holes reduce to those given by Shraiman and Siggia for the t-J model. This provides a link between the weak- and the strong-coupling theories of the doped quantum antiferromagnets, in the small-doping limit.We reconsider some of the previous studies of the interactions between the holes and the spin background in the Hubbard model in the small-doping limit. We show that the hole-hole interaction due to the transverse magnetization fluctuations (i.e., spin waves) is finite at arbitrarily small hole density. It may be comparable to the coupling due to the longitudinal magnetization fluctuations (which are the essence of the ``spin-bag'' mechanism of Schrieffer, Wen, and Zhang). This suggests that the two couplings should be considered simultaneously when studying the phase diagram of the lightly doped quantum antiferromagnets at the values of U/t relevant to the high-${\mathit{T}}_{\mathit{c}}$ superconducting materials. We also show that in the large-(U/t) limit the Hubbard-model expressions for the coupling of holes reduce to those given by Shraiman and Siggia for the t-J model. This provides a link between the weak- and the strong-coupling theories of the doped quantum antiferromagnets, in the small-doping limit.

Physical review. B, Condensed matterOct 1, 199041 citations

A one-dimensional model of hole superconductivity

J. Zittartz, Andreas Klümper, Andreas Schadschneider +1 more

Physica B Condensed MatterFeb 1, 19943 citations

Exact ground and excited states of at-Jladder doped with two holes

Indrani Bose, Saurabh Gayen

A two-chain ladder model is considered that is described by the strong-coupling t - t ´- J - J ´ Hamiltonian. For the case of two holes moving in a background of antiferromagnetically interacting spins, exact, analytical results are derived for the ground-state energy and low-lying excitation spectrum. The ground state is a bound state of two holes with total spin S = 0. The charge excitation is gapless and the spin excitation has a gap. The corresponding wave functions are also exactly determined. The bound hole pair is found to have symmetry of the d-wave type. In the limit of strong rung coupling, the model maps onto an effective hard-core-boson model which exhibits dominant superconducting pairing correlations.A two-chain ladder model is considered that is described by the strong-coupling t - t ´- J - J ´ Hamiltonian. For the case of two holes moving in a background of antiferromagnetically interacting spins, exact, analytical results are derived for the ground-state energy and low-lying excitation spectrum. The ground state is a bound state of two holes with total spin S = 0. The charge excitation is gapless and the spin excitation has a gap. The corresponding wave functions are also exactly determined. The bound hole pair is found to have symmetry of the d-wave type. In the limit of strong rung coupling, the model maps onto an effective hard-core-boson model which exhibits dominant superconducting pairing correlations.

arXiv:cond-mat/9812140Journal of Physics Condensed MatterAug 6, 19999 citations

Electron-hole superconductors

Roberto D. Merlin

Solid State CommunicationsSep 1, 19901 citation

Strong-coupling field theory and soliton doping in a one-dimensional copper-oxide model

Victor J. Emery

A field theory for the strong-coupling limit of a one-dimensional copper-oxide model is obtained from a weak-coupling point of view. Complementary aspects of strong correlations and band motion are incorporated in a natural way. Doping induces soliton or antisoliton charge excitations into a state with explicity broken chiral symmetry. The solitons or antisolitons have divergent superconductive pairing-correlation functions and various properties reminiscent of doped holes or electrons in high-temperature superconductors.A field theory for the strong-coupling limit of a one-dimensional copper-oxide model is obtained from a weak-coupling point of view. Complementary aspects of strong correlations and band motion are incorporated in a natural way. Doping induces soliton or antisoliton charge excitations into a state with explicity broken chiral symmetry. The solitons or antisolitons have divergent superconductive pairing-correlation functions and various properties reminiscent of doped holes or electrons in high-temperature superconductors.

Physical Review LettersAug 20, 199037 citations

{\mathit{T}}_{\mathit{c}}

superconducting materials. We also show that in the large-(U/t) limit the Hubbard-model expressions for the coupling of holes reduce to those given by Shraiman and Siggia for the t-J model. This provides a link between the weak- and the strong-coupling theories of the doped quantum antiferromagnets, in the small-doping limit.