Related papers: Unambiguous connection between the Fermi surface t…
Studies of the electronic spectral function in cuprates by Angle-Resolved Photo-Emission Spectroscopy reveal unusual features in the pseudogap phase that persist in the superconducting phase. We address here these observations based on the…
Here we apply high resolution angle-resolved photoemission spectroscopy (ARPES) using a wide excitation energy range to probe the electronic structure and the Fermi surface topology of the Ba1-xKxFe2As2 (Tc = 32 K) superconductor. We find…
The strong correlation effect in cuprate superconductors have greatly enriched the phase diagram showing the co-existence of superconductivity with many intertwined orders. One of the prominent issues concerning the superconductivity…
In the high-temperature ($T_{c}$) cuprate superconductors, increasing evidence suggests that the pseudogap, existing below the pseudogap temperature $T$*, has a distinct broken electronic symmetry from that of superconductivity.…
The electronic structure of single crystals Na$_{0.6}$CoO$_2$, which are closely related to the superconducting Na$_{0.3}$CoO$_2$.$y$H$_2$O ($T_c \sim 5K$), is studied by angle-resolved photoelectron spectroscopy. While the measured Fermi…
Underdoped cuprate superconductors are believed to be strongly correlated with electronic systems with small phase stiffness leading to a large phase fluctuation region is known as the pseudogap state. With increasing doping it is generally…
The effects of structural supermodulation with the period $\lambda \approx26$ \AA \ along the $b$-axis of Bi$_2$Sr$_2$CaCu$_2$O$_{8+\delta}$ have been observed in photoemission studies from the early days as the presence of diffraction…
The angle-resolved photoemission spectroscopy studies on cuprates in the pseudogap region reveal an extraordinary topological transition in which the ground state changes from one with a normal Fermi surface to one with four Fermi points.…
A reduction of the density of states near the Fermi energy in the normal state (pseudogap) of high-temperature oxide superconductors is examined on the basis of the two-dimensional tight-binding model with effective interactions due to…
We use time- and angle-resolved photoemission to measure the nodal non-equilibrium electronic states in various dopings of Bi$_2$Sr$_2$CaCu$_2$O$_{8+\delta}$. We find that the initial pump-induced transient signal of these ungapped states…
The paper compares the K-dependence of the superconducting gap in different doping ranges. The fine behavior of the leading edge gap indicates that the pairing susceptibility is peaked at special regions on the Fermi surface. These hot…
Superconductivity is realized by opening a gap in the superconducting state. The gap symmetry is crucial in understanding the underlying superconductivity mechanism. The magnitude and the phase are essential in fully characterizing the…
In a recent experiment [M. Feld et al., Nature 480, 75 (2011); B. Froehlich et al., Phys. Rev. Lett. 109,130403 (2012)], a pairing gap was detected in a two-dimensional (2D) Fermi gas with attractive interaction at temperatures where…
In order to clarify superconducting properties of BiS$_2$-based layered superconductors LaO$_{1-x}$F$_x$BiS$_2$, we evaluate the superconducting transition temperature $T_{\rm c}$ and analyze the gap function in a weak-coupling limit on the…
The nature of the pseudogap state, observed above the superconducting transition temperature TC in many high temperature superconductors, is the center of much debate. Recently, this discussion has focused on the number of energy gaps in…
We analyze the interplay between the absence or presence of the nodes in the superconducting gap along electron Fermi surfaces (FSs) in Fe-pnictides, and 2Delta/T_c along hole FSs, measured by ARPES. We solve the set of coupled gap…
We present a detailed study of the symmetry and structure of the pairing gap in Fe-based superconductors (FeSC). We treat FeSC as quasi-2D, decompose the pairing interaction in the XY plane in s-wave and d-wave channels into contributions…
We have examined theoretically the electronic band structure and Fermi surface of tetragonal low-temperature superconductor Bi2Pd. Our main results are that (i) the Pd 4d and Bi 6p states determine the main peculiarities of the…
A model with d-wave pairing symmetry is studied by employing a non-perturbative sum rule approach. At low temperature the magnitude of a normal state pseudogap shows strong $\vec{k}$ or angle dependence well fitted by $\cos 2\phi$ form.…
We present a re-examination of the electronic structure and Fermi Surface (FS) of Bi-Sr-Ca-Cu-O (BSCCO) as obtained from angle-resolved photoemission experiments. By applying a stricter set of FS crossing criteria as well as by varying the…