Related papers: Collective modes in singlet superconductors
We study collective modes near the quantum critical point of a pair-density-wave (PDW) superconductor in 2+1 dimensions. The fate of gaps of various collective modes is investigated by functional renormalization. For incommensurate PDW…
We consider a superconducting state with a mixed symmetry order parameter components, e.g. d+is or d+id' with d'= d_{xy}. We argue for the existence of the new orbital magnetization mode which corresponds to the oscillations of relative…
Multi-gap superconductors can exhibit qualitatively new phenomena due to existence of multiple order parameters. Repulsive electronic interactions may give rise to a phase difference of $\pi$ between the phases of the order parameters.…
We show that the two branches of collective modes discovered recently in under-doped Cuprates with huge spectral weight are a necessary consequence of the loop-current state. Such a state has been shown in earlier experiments to be…
Order parameter collective modes are the fingerprint of a condensed phase. The spectroscopy of these modes in superfluid $^3$He and unconventional superconductors can provide key information on the symmetry of the condensate as well as the…
We study the phase diagrams and thermodynamic properties of a system of coexisting itinerant electrons and local pairs (LP), in the presence of diagonal disorder. The model considered takes into account both the charge exchange couplings,…
We consider the large-N Calogero model in the \h\ collective-field approach based on the $1/N$ expansion. The Bogomol'nyi limit appears and the corresponding equation for the semiclassical configuration gives the correct ground-state…
We study two effective models developed for description of superconductors with short-coherence length: (i) the extended Hubbard model with on-site attraction and intersite repulsion, (ii) the model of hard-core charged bosons on a lattice.…
Motivated by the recent controversy surrounding the Kerr effect measurements in strontium ruthenate \cite{xia:167002}, we examine the electromagnetic response of a clean chiral p-wave superconductor. When the contributions of the collective…
We analyze the spectrum of collective modes in a superconductor in which pairing is mediated by long-range nematic fluctuations. Previous experimental and theoretical studies have found that the superconducting gap in such a system is…
Recent advances in momentum-resolved electron energy-loss spectroscopy (MEELS) and resonant inelastic X-ray scattering (RIXS) now allow one to access the charge response function with unprecedented versatility and accuracy. This allows for…
Collective charge density excitation spectra of both a spatially separated two-component quasi-one dimensional (1D) quantum plasma, as existing in a semiconductor double quantum wire structure, and a 1D homogeneous electron-hole plasma, as…
Standard weak coupling methods are used to study collective modes in the superconducting state of a double-layer system with intralayer and interlayer interaction, as well as a Josephson-type coupling and single particle hopping between the…
We study hybridization of collective plasmon and Carlson-Goldman-Artemenko-Volkov modes in a hybrid system, consisting of a two-dimensional layers of electron gas in the normal state and superconductor, coupled by long-range Coulomb forces.…
We investigate the superconducting (SC), charge-density wave (CDW), and antiferromagnetic (AFM) phases in the extended Hubbard model at zero temperature and half-filling. We employ the iterated equations of motion approach to compute the…
The collective mode spectrum of a symmetry-breaking state, such as a superconductor, provides crucial insight into the nature of the order parameter. In this context, we present a microscopic weak-coupling theory for the collective modes of…
Motivated by the recent development of terahertz pump-probe experiments, we investigate the short-time dynamics in superconductors with multiple attractive pairing channels. Studying a single-band square lattice model with spin-spin…
A unitary Fermi gas has a surprisingly rich spectrum of large amplitude modes of the pairing field alone, which defies a description within a formalism involving only a reduced set of degrees of freedom, such as quantum hydrodynamics or a…
We investigate a double layer system with tight-binding hopping, intra-layer and inter-layer interactions, as well as a Josephson like coupling. We find that an antiferromagnetic spin polarization induces additional spin-triplet pairing…
The observation of an unusual spin resonant excitation in the superconducting state of various High-Tc ~copper oxides by inelastic neutron scattering measurements is reviewed. This magnetic mode % (that does not exist in conventional…