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تسجيل مستخدم جديدNodes of the superconducting gap probed by electronic Raman scattering in HgBa_{2}CaCu_{2}O_{6+delta } single crystals
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Pure electronic Raman spectra with no phonon structures superimposed to the electronic continuum, are reported, in optimally doped HgBa_{2}CaCu_{2}O_{6+delta } single crystals (T_{c }=126 K). As a consequence, the spectra in the A_{1g }, B_{1g } and B_{2g } symmetries, including the crucial low energy frequency dependence of the electronic scattering, are directly and reliably measured. The B_{2g } and, most strikingly, the B_{1g } spectra exhibit a strong intrinsic linear term, which suggests that the nodes are shifted from the [110] and [1bar{1}0] directions, a result inconsistent with a pure d_{x^{2}-y^{2}} model.
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Pure electronic Raman spectra with no phonon structures superimposed to the electronic continuum, are reported for the first time, in optimally doped $HgBa_{2}CaCu_{2}O_{6+delta } $ single crystals $(T_{c }=126 $ K). Our low temperature spectra (15 K
) for the $A_{1g}$, $B_{1g} $ and $B_{2g} $ symmetries exhibit striking differences with previous data in $Bi_{2}Sr_{2}CaCu_{2}O_{8+delta }. $ The shape of the spectra for the various symmetries cannot be fitted by Devereauxs $d_{x^{2}-y^{2}} $ calculations, but strongly suggests a $d_{x y } $ gap, with its minima in the [100] and [010] directions.
A complete knowledge of its excitation spectrum could greatly benefit efforts to understand the unusual form of superconductivity occurring in the lightly hole-doped copper-oxides. Here we use tunnelling spectroscopy to measure the Tto 0 spectrum of
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We present realistic multiband calculations of scanning tunneling spectra in Bi_{2}Sr_{2}CaCu_{2} O_{8+delta} over a wide doping range. Our modeling incorporates effects of a competing pseudogap and pairing gap as well as effects of strong electronic
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Measurements of non-local in-plane resistance originating from transverse vortex-vortex correlations have been performed on a Bi_{2}Sr_{2}CaCu_{2}O_{8+delta} high-T_c superconductor in a magnetic field up to 9 T applied along the crystal c-axis. Our
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