Related papers: Spectroscopic evidence of nematic fluctuations in …
We report the evolution of the electronic nematic susceptibility in FeSe via Raman scattering as a function of hydrostatic pressure up to 5.8 GPa where the superconducting transition temperature $T_{c}$ reaches its maximum. The critical…
We present a high-pressure NMR study of the overdoped iron pnictide superconductor NaFe$_{0.94}$Co$_{0.06}$As. The low-energy antiferromagnetic spin fluctuations in the normal state, manifest as the Curie-Weiss upturn in the spin-lattice…
Normal state superconducting fluctuations are calculated for the case of a tight binding bandstructure. The resulting electronic self energy and spectral weight are anisotropic on the Fermi surface. For certain values of the chemical…
The role of nematic order for the mechanism of high-temperature superconductivity is highly debated. In most iron-based superconductors (IBS) the tetragonal symmetry is broken already in the normal state, resulting in orthorhombic lattice…
Defects in LiFeAs are studied by scanning tunneling microscopy (STM) and spectroscopy (STS). Topographic images of the five predominant defects allow the identification of their position within the lattice. The most commonly observed defect…
Unconventional superconductivity often intertwines with various forms of order, such as the "nematic" order which breaks the rotational symmetry of the lattice. Investigation of these ordered phases sheds crucial light on the…
An oscillatory magnetic field dependence of the DC voltage is observed when a low-frequency current flows through superconducting Sn-Ge thin-film composites near the percolation threshold. The paper also studies the experimental…
The unusual quantum-disordered magnetic ground state intertwined with superconductivity and electronic nematicity in FeSe has been a research focus in iron-based superconductors. However, the intrinsic spin excitations across the entire…
Interactions between nematic fluctuations, magnetic order and superconductivity are central to the physics of iron-based superconductors. Here we report on in-plane transverse acoustic phonons in hole-doped Sr$_{1-x}$Na$_x$Fe$_2$As$_2$…
From first-principles calculations, we have studied the electronic and magnetic structures of the ground state of LaOFeAs. The Fe spins are found to be collinear antiferromagnetic ordered, resulting from the interplay between the strong…
Motivated by a recent experiment in ultracold atoms [ S. Krinner et al., Proc. Natl. Acad. Sci. U.S.A 113, 8144 (2016)], we analyze transport of attractively interacting fermions through a one-dimensional wire near the superfluid…
Inelastic scattering of visible light (Raman effect) offers a window into properties of correlated metals such as spin, electron and lattice dynamics as well as their mutual interactions. In this review we focus on electronic and spin…
An investigation of possibilities for superconductivity mediated by spin fluctuations in some elementary metals is motivated by the recent discovery of superconductivity in the hcp high-pressure phase of iron. The electronic structure, the…
We present $^{77}$Se-NMR measurements on FeSe$_{1-x}$S$_x$ samples with sulfur content $x=0,9,15$ and $29\%$. Twinned nematic domains are observed in the NMR spectrum for all samples except $x=29\%$. The NMR spin-lattice relaxation rate…
Spin fluctuations in superconducting BaFe2(As1-xPx)2 (x=0.34, Tc = 29.5 K) are studied using inelastic neutron scattering. Well-defined commensurate magnetic signals are observed at ({\pi},0), which is consistent with the nesting vector of…
Increasingly intricate phase diagrams in new classes of superconductors host fascinating interactions between superconductivity, diverse quantum phases, and quantum critical dynamics. The native superfluids, however, often exhibit much…
This work investigates nematic fluctuations and electronic correlations in the hole-doped iron pnictide superconductor Ba$_{1-x}$K$_x$Fe$_2$As$_2$ by means of longitudinal and transverse elastoresistance measurements over a wide doping…
Between the different families of pnictide multiband superconductors, LiFeAs is probably one of the less understood. Indeed, despite the large amount of experiments performed in the last few years on this material, no consensus has been…
We investigate vortices in LiFeAs using scanning tunneling microscopy/spectroscopy. Zero-field tunneling spectra show two superconducting gaps without detectable spectral weight near the Fermi energy, evidencing fully-gapped multi-band…
Understanding the organizing principles of interacting electrons and the emergence of novel electronic phases is a central endeavor of condensed matter physics. Electronic nematicity, in which the discrete rotational symmetry in the…