Related papers: Universal zero-frequency Raman slope in a d-wave s…
We have analyzed the $B_{1g}$ and $B_{2g}$ Raman spectra of electron-doped cuprate superconductors Nd$_{2-x}$Ce$_{x}$CuO$_4$ and Pr$_{2-x}$Ce$_{x}$CuO$_4$ using a weakly coupled two-band model. One of these two bands is centered around…
The scaling of the conductivity at the superfluid-insulator quantum phase transition in two dimensions is studied by numerical simulations of the Bose-Hubbard model. In contrast to previous studies, we focus on properties of this model in…
Non-resonant microwave absorption(NRMA) studies of superconducting MgB_2 at a frequency of 9.43 GHz in the field range -50 Gauss to 5000 Gauss are reported. The NRMA results indicate near absence of intergranular weak links. A linear…
Polarisation-resolved Raman scattering measurements were performed on MgB_2 single crystals to determine the magnitude, symmetry and temperature dependence of the superconducting gap. A single sharp peak due to Cooper pair breaking appears…
We study the nonlinear transport properties of NS (normal-superconductor) and NSN structures by means of a self-consistent microscopic description. A nonzero superfluid velocity causes the various quasiparticle channels within S to open at…
In a unified approach we consider transport properties of 1D and quasi-1D waveguides with rough surfaces. Main attention is paid to the possibility of perfect transmission of waves due to specific long-range correlations in the surface…
We study the Wiedemann-Franz (WF) law in the d-density wave (DDW) model. Even though the opening of the DDW gap $(W_{0})$ profoundly modifies the electronic density of states and makes it dependent on energy, the value of the WF ratio at…
To clarify the order parameter symmetry of cuprates, the magnetic penetration depth $\lambda$ was measured along the crystallographic directions $a$, $b$, and $c$ in single crystals of YBa$_2$Cu$_4$O$_8$ via muon spin rotation. This method…
Calculations are presented of the in-plane far-infrared conductivity of a d_{x^2-y^2}-wave superconductor, incorporating elastic scattering due to impurities and inelastic scattering due to spin fluctuations. The impurity scattering is…
One of the remarkable features of disordered d-wave superconductors is strong sensitivity of long range properties to the microscopic realization of the disorder potential. Particularly rich phenomenology is observed for the --…
The low-energy spectrum of graphene nanoribbons with armchair edges (armchair nanoribbons) is described as the superposition of two non-equivalent Dirac points of graphene. In spite of the lack of well-separated two valley structures, the…
We calculate the infrared conductivity of a stack of coupled, two-dimensional superconducting planes within the Fermi liquid theory of superconductivity. We include the effects of random scattering processes and show that the presence of…
We develop a theory of the conductance of superconductor/normal metal/superconductor junctions in the case where the superconducting order parameter has d-wave symmetry. At low temperature the conductance is proportional to the square root…
We investigate the electronic Raman scattering in pure, quasi-one dimensional conductors with density wave ground state. In particular, we develop the theory of light-scattering on spin and charge density waves, both conventional and…
We reexamine the possibility of d-wave superconductivity in the hole-doped two-dimensional Hubbard model. In terms of the gauge field description of the spin fluctuations, we show that d-wave superconductivity is unstable in the…
The bulk microwave conductivity of a dirty d-wave superconductor is known to depend sensitively on the range of the disorder potential: long-range scattering enhances the conductivity, while short- range scattering has no effect. Here we…
The spin-density wave (SDW) can be considered as a pair of charge density waves (CDWs), one composed only of electrons with up-spins and the other only of electrons with down-spins. The high-temperature superconductivity found in cuprates…
Motivated by Sr2RuO4, we consider a chiral superconductor where the gap is strongly suppressed along certain momentum directions. We evaluate the thermal Hall conductivity in the gapless regime, i.e., at temperature small compared with the…
Motivated by recent transport and neutron scattering experiments suggesting an orientational symmetry breaking in underdoped cuprates we present a theoretical study of Raman scattering near a d-wave Pomeranchuk instability (PI). The d-wave…
The superconducting state of underdoped cuprates is often described in terms of a single energy-scale, associated with the maximum of the (d-wave) gap. Here, we report on electronic Raman scattering results, which show that the gap function…