Comment on "Unconventional s-wave superconductivity in Fe(Se,Te)"
arXiv:1007.0047
Abstract
Hanaguri et al (Science, 8th of January 2010, p. 181) have reported STM measurements on an Fe-based superconductor Fe(Se,Te). After Fourier-transforming their data they found three sets of sharp peaks in the reciprocal space. They interpreted one as a Bragg peak (an umklapp scattering) and two as resulting from quasiparticle interference (QPI) We point out that at least one of these two peaks is also a Bragg peak, corresponding to another reciprocal lattice vector, and therefore is not a QPI peak, and the third peak has similar structure, too sharp for a QPI peak in a nodeless superconductor with an isotropic gap, proposed by Hanaguri et al. We argue that this peak must also be a Bragg peak related to a surface reconstruction doubling the unit cell. We also calculate the QPI pattern, assuming an isotropic gap, and find that indeed it is quite different from the experiment. Finally, we speculate about possible origin of the magnetic field dependence of the Bragg peaks in this compound.
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References in corpus (6)
- Reply to Comment on "Unconventional s-wave superconductivity in Fe(Se,Te)"
- Pressure Induced Static Magnetic Order in Superconducting FeSe_1-x
- Coherence factors in a high-Tc cuprate probed by quasi-particle scattering off vortices
- Anisotropic Structure of the Order Parameter in FeSe0.45Te0.55 Revealed by Angle Resolved Specific Heat
- Atomic and electronic structures of ternary iron arsenides FeAs(001) surfaces (=Ba, Sr, or Ca)
- Comment on "Nematic Electronic Structure in the "Parent" State of the Iron-Based Superconductor Ca(Fe1-xCox)2As2"