Local density of states modulation and scanning tunneling microscopy in cuprate superconductors: Effect of gap anisotropy

Abstract

Recent low-temperature Fourier-transformed scanning tunneling microscopy (FT-STM) data on optimally- and over-doped superconducting Bi2Sr2CaCu2O8 was shown to be an excellent manifestation of good quasiparticles in these samples. Along this line, we extend to study how the gap anisotropy effect can be investigated in the FT-STM images. The case of d(x2-y2)+s-wave gap, which may be relevant to YBa2Cu3O7-delta, is examined in details.