相关论文: Electron-boson spectral density of LiFeAs obtained…
In Part I we discuss accumulating experimental evidence related to the structure and origin of the bosonic spectral function \alpha ^{2}F in high-temperature superconducting (HTSC) cuprates near optimal doping. Some global properties of…
We propose a new formulation for atomic side mode dynamics from super-radiant light scattering of trapped atoms. A detailed analysis of the recently observed super-radiant light scattering from trapped bose gases [S. Inouye {\it et al.},…
We present a new method of determining the anisotropy of the gap function in layered high-Tc superconductors. Careful inelastic neutron scattering measurements at low temperature of the phonon dispersion curves in the (100) direction in…
The lithium ions in Lithium iron arsenide phases with compositions close to LiFeAs have been located using powder neutron diffraction. These phases exhibit superconductivity at temperatures at least as high as 16 K demonstrating that…
Several angle resolved photoemission spectroscopy (ARPES) studies reveal a poorly nested Fermi surface of LiFeAs, far away from a spin density wave instability, and clear-cut superconducting gap anisotropies. On the other hand a very…
Electron-boson coupling plays a key role in superconductivity for many systems. However, in copper-based high-temperature ($T_c$) superconductors, its relation to superconductivity remains controversial despite strong spectroscopic…
Optical data is encoded with information on the microscopic interaction between charge carriers. For an electron-phonon system, the Eliashberg equations apply and a Kubo formula can be used to get the infrared conductivity. The task of…
We report optical spectroscopic measurements on electron- and hole-doped BaFe2As2. We show that the compounds in the normal state are not simple metals. The optical conductivity spectra contain, in addition to the free carrier response at…
We report here first extensive measurements of the temperature dependence of phonon density of states of BaFe2As2, the parent compound of the newly discovered FeAs-based superconductors, using inelastic neutron scattering. The experiments…
Very high energy resolution photoemission experiments on high quality samples of optimally doped Bi$_2$Sr$_2$CaCu$_2$O$_{8+\delta}$ show new features in the low-energy electronic excitations. A marked change in the binding energy and…
A century on from its discovery, a complete fundamental understanding of superconductivity is still missing. Considerable research efforts are currently devoted to elucidating mechanisms by which pairs of electrons can bind together through…
We report results of microwave surface impedance measurements of LiFeAs single crystals. The in-plane penetration depth depends on temperature exponentially at low temperatures, which strongly suggests that this material has the nodeless…
We calculate the spectral density of the phi meson in a hot bath of nucleons and pions using a general formalism relating self-energy to the forward scattering amplitude (FSA). In order to describe the low energy FSA, we use experimental…
The in-plane infrared and visible (3 meV-3 eV) reflectivity of Bi2Sr2CaCu2O8+d (Bi-2212) thin films is measured between 300 K and 10 K for different doping levels with unprecedented accuracy. The optical conductivity is derived through an…
A d-wave, Eliashberg analysis of break junction and STM tunneling spectra on BiSrCaCuO (Bi2212) reveals that a spectral dip feature is directly linked to strong electronic coupling to a narrow boson spectrum, evidenced by a large peak in…
We have fabricated c-axis point contact junctions between high-quality LiFeAs single crystals and Pb or Au tips in order to study the nature of the superconducting order parameter of LiFeAs, one of the few stoichiometric iron-based…
We analyze results for the Boson Peak from the neutron time of flight spectroscopy data on Ge-As-Se, and Raman spectra data on m-TCP and OTP, using a recent mode coupling model that takes into account the coupling of density fluctuations…
We report multi-epoch VLA H I absorption observations of the source 1741-038 (OT-068) before and during an extreme scattering event (ESE). Observations at four epochs, three during the ESE, were obtained. We find no changes in the…
We develop a strong-coupling ($t \ll U$) expansion technique for calculating the density profile for bosonic atoms trapped in an optical lattice with an overall harmonic trap at finite temperature and finite on site interaction in the…
Among hundreds of spinel oxides, LiTi2O4 (LTO) is the only one that exhibits superconductivity (Tc ~13 K). Although the general electron-phonon coupling is still the main mechanism for electron pairing in LTO, unconventional behaviors such…