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تسجيل مستخدم جديدElectron-boson glue function derived from electronic Raman scattering
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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 spectroscopy (ARPES), electronic properties are measured along well-defined directions in momentum space rather than their weighted averages. In contrast, the optical conductivity involves a momentum average over the entire Brillouin zone. Newly measured Raman response data on high-quality Bi$_2$Sr$_2$CaCu$_2$O$_{8+delta}$ single crystals up to high energies have been inverted using a modified maximum entropy inversion technique to extract from $B_{1g}$ and $B_{2g}$ Raman data corresponding electron-boson spectral densities (glue) are compared to the results obtained with known ARPES and optical
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