Related papers: Material-specific gap function in the high-tempera…
We theoretically study superconducting proximity effect between a topological insulator (TI) and a high-temperature d-wave superconductor (dSC). When the TI-dSC heterostructure violates 90 degree-rotation and certain reflection symmetries,…
A brief history is offered concerning the relation of magnetism to superconductivity, and the possibility that magnetic correlations are responsible for certain types of superconductors. A central focus is on high temperature cuprate…
We show that in a superconductor where two or more bands cross the Fermi level it is possible, in the framework of the conventional (s-wave) BCS theory, that the sign of the superconducting gap is different on the different sheets of the…
The interplay between the band Jahn-Teller distortion and the superconductivity is studied for the system whose Fermi level lies in two-fold degenerate band. Assuming that the lattice distortion is coupled to the orbital electron density…
A number of recent experiments have suggested the presence of either real or complex components in the gap symmetry of high-$T_c$ superconductors (HTSC). In this paper we introduce a novel approach to study the competition of such complex…
Deviations from Fermi liquid behavior are well documented in the normal state of the cuprate superconductors, and some of these differences are possibly related to pre-formed pairs appearing at temperatures above T_c. In order to test these…
We present electron-tunneling spectroscopy of slightly overdoped Bi2212 single crystals at low temperature using a break-junction technique. Below Tc, we observe, at least, two different superconducting gaps. We show that (i) the largest…
We discuss the high-temperature superconductivity in copper oxide ceramics. We propose an effective Hamiltonian to describe the dynamics of electrons or holes injected into the copper oxide layers. We show that our approach is able to…
We present the theory of the leading edge gap in the normal state of underdoped high-$T_c$ materials. The consideration is based on a magnetic scenario for cuprates. We show that as doping decreases, the increasing interaction with…
The square-lattice Hubbard and closely related $t$-$J$ models are considered as basic paradigms for understanding strong correlation effects and unconventional superconductivity (SC). Recent large-scale density matrix renormalization group…
We study the quantum corrections to the Fermi energy of a two-dimensional electron system, showing that it is attracted towards the Van Hove singularity for a certain range of doping levels. The scaling of the Fermi level allows to cure the…
Singlet pairing in a Fermi superfluid is frustrated when the amounts of fermions of each pairing partner are unequal. The resulting `imbalanced superfluid' has been realized experimentally for ultracold atomic gases with s-wave…
The two gaps in a two-band clean s-wave superconductor are evaluated self-consistently within the quasiclassical Eilenberger weak-coupling formalism with two in-band and one inter-band pairing potentials. Superfluid density, free energy and…
A new method for estimating the parameter ensuring the fulfillment of the Mermin-Wagner theorem in the strong coupling diagram technique (SCDT) for the two-dimensional Hubbard model is suggested. With the precise parameter value, calculated…
Three-dimensional $d$-wave ($j=2$) superconducting state may result from Cooper pairing in channels with different angular momenta and spin, such as $(l=0, s=2)$ or $(l=2, s=0)$. We consider spin-3/2 Luttinger fermions in the limit of small…
We consider a strongly repulsive fermionic gas in a two-dimensional optical lattice confined by a harmonic trapping potential. To address the strongly repulsive regime, we consider the $t-J$ Hamiltonian. The presence of the harmonic…
Assuming a phenomenological self-energy $Im \Sigma(\omega) \sim |\omega|^{\beta\}, (\beta=1 $), which becomes gapped below $T_c$, we derived a new gap equation. The new gap equation contains the effect of the kinetic energy gain upon…
In this paper we study the effects of the strong coupling superconductivity on the normal state electronic structure. We point out that the pseudogap phenomena in High-T_c cuprates are naturally explained as a precursor of the strong…
Thermal conductivity and specific heat were measured in the superconducting state of the heavy fermion material Ce_{1-x}La_{x}CoIn_{5}. With increasing impurity concentration x, the suppression of T_{c} is accompanied by the increase in the…
The experimentally observed difference of superconducting critical temperature $T_{c}$ in hole-doped cuprates is studied by using an extended interlayer coupling model for layered d-wave superconductors. We show that the change of the…