TUNNELING SPECTROSCOPY OF PHONON STRUCTURES IN BI2SR2CACU2O8 SINGLE-CRYSTALS

Using the break-junction technique tunneling spectra have been measure d on Bi2Sr2CaCu2O8 single crystals in magnetic fields up to 20 T. The tunneling junctions exhibited low leakage currents and well developed gap structures. Structures were found at voltages corresponding to the phonon-frequency range. The main shape of the spectra can be reasonab ly compared with the inelastic neutron scattering data of the phonon d ensity of states. From the Rowell-McMillan inversion of the tunneling data, the Eliashberg function alpha(2)F(omega) for the electron-phonon coupling was obtained.