The two‐dimensional t‐J model in a staggered field is studied by exact diagonalization up to 20 sites. For the low‐hole‐density region and a realistic value of J/t, it is found that the presence of a staggered field strengthens the attraction between two holes. With increasing field, the dx2−y2‐wave superconducting correlations are enhanced while the extended‐s‐wave ones hardly change. This implies that coexistence of the dx2−y2‐wave superconducting order and the commensurate antiferromagnetic order occurs in a staggered field.The two‐dimensional t‐J model in a staggered field is studied by exact diagonalization up to 20 sites. For the low‐hole‐density region and a realistic value of J/t, it is found that the presence of a staggered field strengthens the attraction between two holes. With increasing field, the dx2−y2‐wave superconducting correlations are enhanced while the extended‐s‐wave ones hardly change. This implies that coexistence of the dx2−y2‐wave superconducting order and the commensurate antiferromagnetic order occurs in a staggered field.

AIP conference proceedingsJan 1, 20030 citations

Exact solution of a one-dimensional model of hole superconductivity

R. Z. Bariev, Andreas Klümper, Andreas Schadschneider +1 more

A new integrable model of a strong correlated electronic system is formulated as a model of hole superconductivity. The model is solved by using the Bethe ansatz. The critical exponents describing the decrease of correlation functions on long distances are derived. The behaviour of these correlations indicates that Cooper pairs of holes are formed in the repulsive region of the model. This conclusion is also confirmed by the calculation of the conductivity and the effective transport mass. In the attractive region, the model is a highly conducting system in which the current carriers with small effective mass are 'light fermions'.A new integrable model of a strong correlated electronic system is formulated as a model of hole superconductivity. The model is solved by using the Bethe ansatz. The critical exponents describing the decrease of correlation functions on long distances are derived. The behaviour of these correlations indicates that Cooper pairs of holes are formed in the repulsive region of the model. This conclusion is also confirmed by the calculation of the conductivity and the effective transport mass. In the attractive region, the model is a highly conducting system in which the current carriers with small effective mass are 'light fermions'.

Journal of Physics A Mathematical and GeneralMar 7, 199368 citations

Hole superconductivity in the dilute limit

F. Marsiglio, J. E. Hirsch

Physica C SuperconductivityNov 1, 199037 citations

Magnetic and transport properties of a coupled Hubbard bilayer with electron and hole doping

Karim Bouadim, G. G. Batrouni, F. Hébert +1 more

The single band, two-dimensional Hubbard Hamiltonian has been extensively studied as a model for high temperature superconductivity. While quantum Monte Carlo simulations within the dynamic cluster approximation are now providing considerable evidence for a $d$ -wave superconducting state at low temperature, such a transition remains well out of reach of finite lattice simulations because of the ``sign problem.'' We show here that a bilayer Hubbard model, in which one layer is electron doped and one layer is hole doped, can be studied to lower temperatures and exhibits an interesting signal of $d$ -wave pairing. The results of our simulations bear resemblance to a recent report on the magnetic and superconducting properties of ${\mathrm{Ba}}_{2}{\mathrm{Ca}}_{3}{\mathrm{Cu}}_{4}{\mathrm{O}}_{8}{\mathrm{F}}_{2}$ which contains both electron and hole doped $\mathrm{Cu}{\mathrm{O}}_{2}$ planes. We also explore the phase diagram of bilayer models in which each sheet is at half-filling.The single band, two-dimensional Hubbard Hamiltonian has been extensively studied as a model for high temperature superconductivity. While quantum Monte Carlo simulations within the dynamic cluster approximation are now providing considerable evidence for a $d$-wave superconducting state at low temperature, such a transition remains well out of reach of finite lattice simulations because of the ``sign problem.'' We show here that a bilayer Hubbard model, in which one layer is electron doped and one layer is hole doped, can be studied to lower temperatures and exhibits an interesting signal of $d$-wave pairing. The results of our simulations bear resemblance to a recent report on the magnetic and superconducting properties of ${\mathrm{Ba}}_{2}{\mathrm{Ca}}_{3}{\mathrm{Cu}}_{4}{\mathrm{O}}_{8}{\mathrm{F}}_{2}$ which contains both electron and hole doped $\mathrm{Cu}{\mathrm{O}}_{2}$ planes. We also explore the phase diagram of bilayer models in which each sheet is at half-filling.

arXiv:0802.0909Physical Review BApr 30, 200850 citations

Exactly soluble model for superconductors with electron-hole coupling

I. G. Brankov, N. S. Tonchev

Jan 1, 19740 citations

d

-wave superconducting state at low temperature, such a transition remains well out of reach of finite lattice simulations because of the ``sign problem.'' We show here that a bilayer Hubbard model, in which one layer is electron doped and one layer is hole doped, can be studied to lower temperatures and exhibits an interesting signal of

d

-wave pairing. The results of our simulations bear resemblance to a recent report on the magnetic and superconducting properties of

{\mathrm{Ba}}_{2}{\mathrm{Ca}}_{3}{\mathrm{Cu}}_{4}{\mathrm{O}}_{8}{\mathrm{F}}_{2}

which contains both electron and hole doped

\mathrm{Cu}{\mathrm{O}}_{2}

planes. We also explore the phase diagram of bilayer models in which each sheet is at half-filling.