Identification of<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi>p</mml:mi></mml:math>-wave superconductors

Buchholtz, Louis J.; Zwicknagl, Gertrud

doi:10.1103/physrevb.23.5788

Cited by 395 publications

(297 citation statements)

References 6 publications

Supporting

Mentioning

292

Contrasting

Order By: Relevance

“…Unconventional superconductors support the existence of zero energy, current carrying surface Andreev bound states (ABS). [39] These states are a direct consequence of the sign change in the d-wave order parameter. [95].…”

Section: Surface Andreev Bound Statesmentioning

confidence: 99%

Magnetic penetration depth in unconventional superconductors

Prozorov

Giannetta

2006

Supercond. Sci. Technol.

404

438

View full text Add to dashboard Cite

Abstract. This topical review summarizes various features of magnetic penetration depth in unconventional superconductors. Precise measurements of the penetration depth as a function of temperature, magnetic field and crystal orientation can provide detailed information about the pairing state. Examples are given of unconventional pairing in hole-and electron-doped cuprates, organic and heavy fermion superconductors. The ability to apply an external magnetic field adds a new dimension to penetration depth measurements. We discuss how field dependent measurements can be used to study surface Andreev bound states, nonlinear Meissner effects, magnetic impurities, magnetic ordering, proximity effects and vortex motion. We also discuss how penetration depth measurements as a function of orientation can be used to explore superconductors with more than one gap and with anisotropic gaps. Details relevant to the analysis of penetration depth data in anisotropic samples are also discussed.Keywords: penetration depth, unconventional superconductivity, pairing symmetry IntroductionThe early suggestion that high temperature superconductors might exhibit unconventional, d-wave pairing, [24,11,154,8] has lead to a wide variety of new experimental probes with sensitivity sufficient to test this hypothesis. The pioneering work of Hardy and coworkers demonstrated that high resolution measurements of the London penetration depth could detect the presence of nodal quasiparticles characteristic of a d-wave pairing state [87]. Since that time, a large number of new superconductors have been discovered, many of which exhibit nontrivial departures from BCS behavior. As we show in this review, penetration depth measurements can be used to examine not only nodal quasiparticles but two-gap superconductivity, anisotropy of the energy gap, Andreev surface states, nonlinear Meissner effect, interplane transport, proximity coupled diamagnetism, vortex matter and the coexistence of magnetism and superconductivity, to name several problems of current interest.

show abstract

Section: Surface Andreev Bound Statesmentioning

confidence: 99%

Magnetic penetration depth in unconventional superconductors

Prozorov

Giannetta

2006

Supercond. Sci. Technol.

404

438

View full text Add to dashboard Cite

show abstract

“…An important consequence of an order parameter showing a sign change (or π phase shift) in different k-directions, is the formation of Andreev bound states at zero energy confined to the surface. Andreev bound states have been discussed first in the context of tunneling into unconventional superconductors by Buchholtz and Zwicknagel [5]. Later on, the formation of Andreev bound states or midgap surface states having zero energy with respect to the Fermi energy and sizable areal density as a consequence of a d x 2 −y 2 -symmetry of the order parameter has been predicted by Hu [6].…”

Section: Introductionmentioning

confidence: 99%

Andreev bound states in high temperature superconductors

et al. 1998

View full text Add to dashboard Cite

Abstract. Andreev bound states at the surface of superconductors are expected for any pair potential showing a sign change in different k-directions with their spectral weight depending on the relative orientation of the surface and the pair potential. We report on the observation of Andreev bound states in high temperature superconductors (HTS) employing tunneling spectroscopy on bicrystal grain boundary Josephson junctions (GBJs). The tunneling spectra were studied as a function of temperature and applied magnetic field. The tunneling spectra of GBJ formed by YBa2Cu3O 7−δ (YBCO), Bi2Sr2CaCu2O 8+δ (BSCCO), and La1.85Sr0.15CuO4 (LSCO) show a pronounced zero bias conductance peak that can be interpreted in terms of Andreev bound states at zero energy that are expected at the surface of HTS having a d-wave symmetry of the order parameter. In contrast, for the most likely s-wave HTS Nd1.85Ce0.15CuO4−y (NCCO) no zero bias conductance peak was observed. Applying a magnetic field results in a shift of spectral weight from zero to finite energy. This shift is found to depend nonlinearly on the applied magnetic field. Further consequences of the Andreev bound states are discussed and experimental evidence for anomalous Meissner currents is presented.

show abstract

“…In unconventional superconductors, the bound states arising from ordinary potential scattering were first considered by Buchholtz and Zwicknagl [5]. They concentrated on the Balian-Werthamer state, which has a hard energy gap, but the momentum-averaged gap vanishes: k ∆( k) = 0, where the sum is over the Fermi surface.…”

Section: Introductionmentioning

confidence: 99%

Bound states and impurity averaging in unconventional superconductors

Joynt

1997

J Low Temp Phys

View full text Add to dashboard Cite

The question of anomalous transport due to a band of impurity states in unconventional superconductors is discussed. In general, the bound state energies are not in midgap, even in the unitarity limit. This implies that, generically, the states associated with impurities are broad resonances, not true bound states. There is no impurity band in the usual sense of the phrase.The wavefunctions of these resonances possess interesting anisotropies in real space, but this does not result in anomalous hopping between impurities.I conclude that the system of resonances produces no qualitative modifications to the T-matrix theory with impurity averaging which is normally used to treat the low-temperature transport of unconventional superconductors.However, users of this method often assume a density of states which is symmetric around the chemical potential. This is not normally the case. It is found that the non-crossing approximation is not valid in a strictly twodimensional system.

show abstract

Identification ofp-wave superconductors

Cited by 395 publications

References 6 publications

Magnetic penetration depth in unconventional superconductors

Magnetic penetration depth in unconventional superconductors

Andreev bound states in high temperature superconductors

Bound states and impurity averaging in unconventional superconductors

Contact Info

Product

Resources

About