The effects of spin fluctuations on the tunneling spectroscopy in High-T_c Superconductors

We investigate the effects of spin fluctuations on the tunneling spectra of the NS junction. In the high junction resistance limit, the dip/hump structure observed in ARPES data for the high Tc superconductors is reproduced in a RPA treatment of the t-t'-J model. It is shown that the dip/hump structure weakens as doping increases as reflected in the data. In the other limit, we predict that the zero bias Andreev peak can coexist with the dip/hump structure. Furthermore, the c-axis tunneling spectra is found to be very similar to a recent STM data once these fluctuations are included.