Related papers: Raman scattering from a superconductivity-induced …
Within the two-orbital model for BiS$_{2}$-based superconductors, the effect from a single nonmagnetic impurity scattering on the superconducting-state is investigated in terms of the T-matrix approach. By considering three kinds of the…
We discuss the possible existence a spin singlet excitation with charge $\pm2$ ($\eta$-mode) originating the $A_{1g}$ Raman resonance in cuprate superconductors. This $\eta$-mode relates the $d$-wave superconducting singlet pairing channel…
We calculate the spin susceptibility at and below T_c for a d_{x^2-y^2}-wave superconductor with resonant impurity scattering and Coulomb correlations. Both the impurity scattering and the Coulomb correlations act to maintain peaks in the…
We argue that the Raman intensity in a spin S two-leg spin-ladder has a pseudo-resonance peak, whose width is very small at large S. The pseudo-resonance originates from the existence of a local minimum in the magnon excitation spectrum,…
When wave scattering systems are subject to certain symmetries, resonant states may decouple from the far-field continuum; they remain localized to the structure and cannot be excited by incident waves from the far field. In this work, we…
We study the consequences of an electron-phonon ($e$-$ph$) interaction that is strongly peaked in the forward scattering ($\mathbf{q} = 0$) direction in a two-dimensional superconductor using Migdal-Eliashberg theory. We find that strong…
We report interesting anomalies in the temperature dependent Raman spectra of FeSe$_{0.82}$ measured from 3K to 300K in the spectral range from 60 to 1800 cm$^{-1}$ and determine their origin using complementary first-principles density…
We present a high-resolution resonance Raman study of hBN encapsulated MoSe$_2$ and WSe$_2$ monolayers at 4 K using excitation energies from 1.6 eV to 2.25 eV. We report resonances with the WSe$_2$ A2s and MoSe$_2$ A2s and B2s excited…
We study the Raman spectra of spin-triplet superconductors in Sr$_2$RuO$_4$. The p-wave and f-wave symmetries are considered. We show that there is the clapping mode with frequency of $\sqrt{2} \Delta(T)$ and $1.02 \Delta(T)$ for p-wave and…
State-of-the-art model Hamiltonians, like Fr\"ohlich's, or density functional theory approaches to electron-phonon interaction suffer from a severe overscreening error. This is due to the incorrect treatment of the screening of the ionic…
We use tunable laser based Angle Resolved Photoemission Spectroscopy to study the electronic structure of the multi-band superconductor, MgB2. These results form the base line for detailed studies of superconductivity in multi-band systems.…
The superconducting gap of MgB2 has been studied by high-resolution angle-resolved photoemission spectroscopy (ARPES). The momentum(k)-resolving capability of ARPES enables us to identify the s- and p-orbital derived bands predicted from…
We investigate the effect of isotope substitution on the electron-phonon interaction in the multi-band superconductor MgB2 using tunable laser based Angle Resolved Photoemission Spectroscopy. The kink structure around 70 meV in the $\sigma$…
We show that the low-energy peak in the polarized resonant Raman spectra of quantum wires, which is commonly associated with ``single particle excitations'', can be interpreted as signature of intra-band collective spin excitations. A broad…
A multiband superconductor with a conventional phonon mechanism can develop an unconventional state with a nontrivial order parameter phase relation between the individual bands. We propose that such a state can explain recent experimental…
We identify universal properties of the low-energy subspace of a wide class of quantum optical models in the ultrastrong coupling limit, where the coupling strength dominates over all other energy scales in the system. We show that the…
The sharp forward electron-phonon $(FEP)$ and impurity $(FIS)$ scattering change the normal and superconducting properties significantly. The pseudo-gap like features are present in the density of states for $\omega <\Omega $, where $\Omega…
In superconductors on triangle lattices, we show that the electronic Raman spectra in the non-resonant channel are independent of the light polarization configuration in the scattering. Therefore the light polarization configuration is no…
A qualitative study of the electron-phonon interaction (EPI) spectra in $2H-NbS{{e}_{2}}$ is carried out by the method of point-contact spectroscopy in the superconducting state. Anisotropy of the EPI spectra for contacts oriented in the…
Hyper-Raman scattering spectra of vitreous B$_2$O$_3$ are reported and compared to Raman scattering results. The main features are indexed in terms of vibrations of structural units. Particular attention is given to the low frequency boson…