The Tunneling Spectroscopy and Shot Noise in Normal Metal-insulator-d-wave Superconductor Junctions

Taking into account the scattering effect of the insulator in normal metal-insulator-d-wave superconductor junctions, and using the Bogoliubov-de Gennes equation and the Blonder-Tinkham-Klapwijk model, we calculate the differential conductance and shot noise. It is shown that,(1)the zero-bias conductance peak will become more sharp; (2) the position of thedifferential shot noise peak is moved to zero-bias; (3) the shot noise power to current ratio will tend to 2e value in higher bias, with the barrier height and width of the insulator increased.