Fourier transform spectroscopy of d-wave quasiparticles in the presence of atomic scale pairing disorder

Abstract

The local density of states power spectrum of optimally doped Bi${}_2$Sr${}_2$CaCu${}_2$O${}_{8+x}$ (BSCCO) has been interpreted in terms of quasiparticle interference peaks corresponding to an "octet'' of scattering wave vectors connecting k-points where the density of states is maximal. Until now, theoretical treatments have not been able to reproduce the experimentally observed weights and widths of these "octet'' peaks; in particular, the predominance of the dispersing "q${}_1$'' peak parallel to the Cu-O bond directions has remained a mystery. In addition, such theories predict "background'' features which are not observed experimentally. Here, we show that most of the discrepancies can be resolved when a realistic model for the out-of-plane disorder in BSCCO is used. Weak extended potential scatterers, which are assumed to represent cation disorder, suppress large-momentum features and broaden the low-energy "q${}_7$''-peaks, whereas scattering at order parameter variations, possibly caused by a dopant-modulated pair interaction around interstitial oxygens, strongly enhances the dispersing "q${}_1$''-peaks.

7 pages, 3 figures

References in corpus (4)

• Inhomogeneity Induces Resonance Coherence Peaks in Superconducting BSCCO
• STM/STS Study on 4a X 4a Electronic Charge Order of Superconducting Bi2Sr2CaCu2O8+d
• Local Density of States and Angle-Resolved Photoemission Spectral Function of an Inhomogeneous D-wave Superconductor
• Modulation of the local density of states within the $d$-density wave theory in the underdoped cuprates