Binding energy of a Cooper pairs with non-zero center of mass momentum in d-wave superconductors

The binding energy of Cooper pairs has been calculated for the case of d-wave symmetry of the superconducting gap in layered cuprate superconductors. We assume that Cooper pairs are formed by the short range potential and then derive the binding energy in the form Δkq = Δx (q) cos kx a + Δy (q) cos ky a + Ωx (q) sin kx a + Ωy (q) sin ky a, where q is a total momentum of the pair. Numerical solutions of the self-consistent system of the integral equations for quantities Δx (q), Δy (q) and Ωx (q), Ωy (q) along different lines in qx, qy planes have been obtained. Anisotropy of the depairing total momentum (or depairing current) has been calculated. © 2007 Elsevier B.V. All rights reserved

London penetration depth in the tight binding approximation: Orthorhombic distortion and oxygen isotope effects in cuprates

We present a simple derivation of an expression for the superfluid density $n_s \propto 1/\lambda^2$ in superconductors with the tight binding energy dispersion. The derived expression is discussed in detail because of its distinction from the known expressions for ordinary superconductors with parabolic energy dispersion. We apply this expression for the experimental data analysis of the isotope effect in London penetration depth parameter $\lambda$ in the BiSrCuO and YBaCuO family compounds near optimal doping, taking into account the orthorhombic distortion of crystal structure, and estimate the isotopic change of hopping parameters from the experimental data. We point out that $1/\lambda^2$ temperature behaviour is very sensitive to the ratio $2\Delta_m(T=0)/ k_B T_c$ and estimate this quantity for a number of compounds.Comment: 10 pages, 4 figure

Binding energy of a Cooper pairs with non-zero center of mass momentum in d-wave superconductors

The binding energy of Cooper pairs has been calculated for the case of d-wave symmetry of the superconducting gap in layered cuprate superconductors. We assume that Cooper pairs are formed by the short range potential and then derive the binding energy in the form Δkq = Δx (q) cos kx a + Δy (q) cos ky a + Ωx (q) sin kx a + Ωy (q) sin ky a, where q is a total momentum of the pair. Numerical solutions of the self-consistent system of the integral equations for quantities Δx (q), Δy (q) and Ωx (q), Ωy (q) along different lines in qx, qy planes have been obtained. Anisotropy of the depairing total momentum (or depairing current) has been calculated. © 2007 Elsevier B.V. All rights reserved

Binding energy of a Cooper pairs with non-zero center of mass momentum in d-wave superconductors

The binding energy of Cooper pairs has been calculated for the case of d-wave symmetry of the superconducting gap in layered cuprate superconductors. We assume that Cooper pairs are formed by the short range potential and then derive the binding energy in the form Δkq = Δx (q) cos kx a + Δy (q) cos ky a + Ωx (q) sin kx a + Ωy (q) sin ky a, where q is a total momentum of the pair. Numerical solutions of the self-consistent system of the integral equations for quantities Δx (q), Δy (q) and Ωx (q), Ωy (q) along different lines in qx, qy planes have been obtained. Anisotropy of the depairing total momentum (or depairing current) has been calculated. © 2007 Elsevier B.V. All rights reserved

Binding energy of a Cooper pairs with non-zero center of mass momentum in d-wave superconductors

The binding energy of Cooper pairs has been calculated for the case of d-wave symmetry of the superconducting gap in layered cuprate superconductors. We assume that Cooper pairs are formed by the short range potential and then derive the binding energy in the form Δkq = Δx (q) cos kx a + Δy (q) cos ky a + Ωx (q) sin kx a + Ωy (q) sin ky a, where q is a total momentum of the pair. Numerical solutions of the self-consistent system of the integral equations for quantities Δx (q), Δy (q) and Ωx (q), Ωy (q) along different lines in qx, qy planes have been obtained. Anisotropy of the depairing total momentum (or depairing current) has been calculated. © 2007 Elsevier B.V. All rights reserved

La Patrie : journal quotidien, politique, commercial et littéraire

30 décembre 19031903/12/30 (A63)

London penetration depth in the tight binding approximation: Orthorhombic distortion and oxygen isotope effects in cuprates

We present a simple derivation of an expression for the superfluid density ns ∝1/ λ2in superconductors with the tight binding energy dispersion. The derived expression is discussed in detail because of its distinction from the known expressions for ordinary superconductors with parabolic energy dispersion. We apply this expression for the experimental data analysis of the isotope effect in London penetration depth parameter λ in the BiSrCuO and YBaCuO family compounds near optimal doping, taking into account the orthorhombic distortion of crystal structure, and estimate the isotopic change of hopping parameters from the experimental data. We point out that 1/λ2 temperature behaviour is very sensitive to the ratio 2Δm(T = 0)/kBTc and estimate this quantity for a number of compounds. © 2010 IOP Publishing Ltd

London penetration depth in the tight binding approximation: Orthorhombic distortion and oxygen isotope effects in cuprates

We present a simple derivation of an expression for the superfluid density ns ∝1/ λ2in superconductors with the tight binding energy dispersion. The derived expression is discussed in detail because of its distinction from the known expressions for ordinary superconductors with parabolic energy dispersion. We apply this expression for the experimental data analysis of the isotope effect in London penetration depth parameter λ in the BiSrCuO and YBaCuO family compounds near optimal doping, taking into account the orthorhombic distortion of crystal structure, and estimate the isotopic change of hopping parameters from the experimental data. We point out that 1/λ2 temperature behaviour is very sensitive to the ratio 2Δm(T = 0)/kBTc and estimate this quantity for a number of compounds. © 2010 IOP Publishing Ltd