Related papers: Electronic crossover suggested by Raman scattering…
Conductivity due to superconducting fluctuations studied in optimally doped YBa2Cu3O7-d films displays a stronger decay law in temperature than explainable by theory. A formula is proposed, which fits the data very well with two…
The effect of Co-Ga paired substitution on the superconducting properties of YBa2Cu3O7-d (Y-123) has been investigated by X-ray diffraction, ac susceptibility,dc resistivity and oxygen content measurements. We report in this paper the…
The electron-doped cuprates were studied by electronic Raman spectroscopy across the entire region of the superconducting (SC) phase diagram. We determined that the magnitude of the SC order parameter varies between 4.6 and 3.5 k_BT_c,…
We formulate a theory for the polarization-dependence of the electronic (pair-breaking) Raman response for the recently discovered non-centrosymmetric superconductors in the clean limit at zero temperature. Possible applications include the…
Study and comparison of over 30 examples of electron doped BaFe2As2 for transition metal (TM) = Co, Ni, Cu, and (Co/Cu mixtures) have lead to an understanding that the suppression of the structural/antiferromagnetic phase transition to low…
We explored by electronic Raman scattering the superconducting state of Bi-2212 single crystal by performing a fine tuned doping study. We found three distinct energy scales in A1g, B1g and B2g symmetries which show three distinct doping…
The effects of planar hole concentration, p, on the resistivity, r(T), of sintered Y1-xCaxBa2(Cu1-yZny)3O7-d samples were investigated over a wide range of Ca, Zn, and oxygen contents. Zn was used to suppress superconductivity and this…
Infrared reflectance measurements were made with light polarized along the a- and c-axis of both superconducting and antiferromagnetic phases of electron doped Nd$_{1.85}$Ce$_{.15}$CuO$_{4+\delta}$. The results are compared to…
We report low energy electronic Raman scattering from Ni-substituted YBa2Cu3O6.95 single crystals with Tc ranging from 92.5 K to 78 K. The fully symmetrical A1g channel and the B1g channel which is sensitive to the dx2-y2 gap maximum have…
The nature of normal state charge-carriers' dynamics and the transition in conduction and gap dimensionalities between 2D and 3D for YBa_2 Cu_3 O_{7-delta} and Bi_2 Sr_2 Ca_{1-x} Y_x Cu_2 O_8 high-T_c superconductors were described by…
Phonon or electron mediated weak BCS attraction is enough to have high critical temperature if a van Hove anomaly is at work. This could apply to electron doped compounds and also to compounds with CuO$_2$ planes overdoped in holes, where…
Electronic Raman scattering studies on MgB2 single crystals as a function of excitation and polarization have revealed three distinct superconducting features: a clean gap below 37 cm-1 and two coherence peaks at 109 cm-1 and 78 cm-1 which…
In this study, we conducted various magnetotransport measurements on Fe$_{1+y}$Te$_{1-x}$Se$_{x}$ single crystals from which excess iron was sufficiently removed. Our results revealed that crossover from the incoherent to the coherent…
Two--magnon Raman scattering is a useful tool to verify recent suggestions concerning the value of the interplanar exchange constant in antiferromagnetic two--layer systems, such as $YBa_2Cu_3O_{6+x}$. We present a theory for Raman…
Recent experiments in underdoped hole-doped cuprates have shown the presence of two energy scales in the Raman spectrum in the superconducting state. This feature has a natural explanation in some models in which pseudogap and…
High-temperature superconductivity in cuprates emerges upon doping the parent Mott insulator. Robust signatures of the low-doped electronic state include a Hall carrier density that initially tracks the number of doped holes and the…
A central issue in the quest to understand the superconductivity in cuprates is the nature and origin of the pseudogap state, which harbours anomalous electronic states such as Fermi arc, charge density wave (CDW), and $d$-wave…
YBa$_2$Cu$_3$O$_{7-\delta}$ (YBCO) has favorable macroscopic superconducting properties of $T_\mathrm{c}$ up to 93 K and $H_{c2}$ up to 150 T. However, its nanoscale electronic structure remains mysterious because bulk-like electronic…
Raman scattering cross sections depend on photon polarization. In the cuprates nodal and antinodal directions are weighted more strongly in $B_{2g}$ and $B_{1g}$ symmetry, respectively. On the other hand in angle-resolved photoemission…
Femtosecond pump probe experiments are reported on quasiparticle relaxation and recombination in YBa2Cu4O8 as a function of temperature and polarization. The data show a 2-component relaxation similar to YBa2Cu3O7-\delta, one component…