Related papers: Pressure induced superconductor quantum critical p…
In multi-band metals quasi-particles arising from different atomic orbitals coexist at a common Fermi surface. Superconductivity in these materials may appear due to interactions within a band (intra-band) or among the distinct metallic…
Superconductivity in strongly correlated systems is a remarkable phenomenon that attracts a huge interest. The study of this problem is relevant for materials as the high $T_c$ oxides, pnictides and heavy fermions. These systems also have…
In multi-band systems, electrons from different orbitals coexist at the Fermi surface. An attractive interaction among these quasi-particles gives rise to inter-band or hybrid pairs which eventually condense in a superconducting state.…
In this work we study a two-band model of a superconductor in a square lattice. One band is narrow in energy and includes local Coulomb correlations between its quasi-particles. Pairing occurs in this band due to nearest neighbor attractive…
In fermionic systems with different types of quasi-particles, attractive interactions can give rise to exotic superconducting states, as pair density wave (PDW) superconductivity and breached pairing. In the last years the search for these…
We explore the temperature effects in the superconducting phases of a hybridized two-band system. We show that for zero hybridization between the bands, there are two different critical temperatures. However, for any finite hybridization…
We consider heterostructures obtained by stacking layers of two s-wave superconductors with significantly different coupling strengths, respectively in the weak- and strong-coupling regimes. The weak- and strong-coupling superconductors are…
Different types of superfluid ground states have been investigated in systems of two species of fermions with Fermi surfaces that do not match. This study is relevant for cold atomic systems, condensed matter physics and quark matter. In…
An enduring question in correlated systems concerns whether superconductivity is favoured at a quantum critical point (QCP) characterised by a divergent quasiparticle effective mass. Despite such a scenario being widely postulated in high…
Multi-band systems as intermetallic and heavy fermion compounds have quasi-particles arising from different orbitals at their Fermi surface. Since these quasi-particles have different masses or densities, there is a natural mismatch of the…
In this paper we study the effects of hybridization in the superconducting properties of a two-band system. We consider the cases that these bands are formed by electronic orbitals with angular momentum, such that, the hybridization…
A considerable success in phenomenological description of high-T$_{\rm c}$ superconductors has been achieved within the paradigm of Quantum Critical Point (QCP) - a parental state of a variety of exotic phases that is characterized by dense…
We study quantum criticality in a holographic Einstein--Maxwell--Dilaton--Axion (EMDA) p-wave superconductor exhibiting a superconductor--insulator transition (SIT). By tracking the superconducting energy gap, we show that approaching the…
The quest for high-temperature superconductivity at ambient pressure is a central issue in physics. In this regard, the relationship between unconventional superconductivity and the quantum critical point (QCP) associated with the…
Chain-like structured superconductive materials (such as A_2Cr_3As_3, with A = K, Rb, Cs) exhibit the multiband electronic structure of single-particle states, where coexisting quasi-one-dimensional (Q1D) and conventional higher-dimensional…
The study of multi-band superconductivity is relevant for a variety of systems, from ultra cold atoms with population imbalance to particle physics, and condensed matter. As a consequence, this problem has been widely investigated bringing…
We investigate superconductivity in a two-dimensional material described by a two-band heavy-fermion model, where hybridization between a dispersive band and a flat band introduces a quasi-flat dispersion to the otherwise localized…
We show that two-band superconductors harbor hidden criticality deep in the superconducting state, stemming from the critical temperature of the weaker band taken as an independent system. For sufficiently small interband coupling $\gamma$…
A two-band Hubbard model is used to describe the band structure and phase separation (PS) in multiband superconductors, especially in cuprates. We predict a large peak in the density of states at the Fermi level in the case of optimum…
We investigate how hybridization (single-quasiparticle scattering) between two superconducting bands induces odd-frequency superconductivity in a multiband superconductor. An explicit derivation of the odd-frequency pairing correlation and…