Atomic Scale Imaging and Spectroscopy of a CuO_2 Plane at the Surface of Bi_2Sr_2CaCu_2O_{8+delta}

TL;DR

This study demonstrates the formation of a stable CuO_2 plane surface on Bi_2Sr_2CaCu_2O_{8+delta} using STM, revealing suppressed conductance likely due to orbital symmetry effects on tunneling.

Contribution

First direct atomic-scale imaging and spectroscopy of a CuO_2 plane at the surface of Bi_2Sr_2CaCu_2O_{8+delta} highlighting its electronic properties.

Findings

CuO_2 plane forms a stable, atomically ordered surface.

Surface exhibits strongly suppressed tunneling conductance at low voltages.

Suppressed conductance may be due to orbital symmetry effects.

Abstract

We have used a scanning tunneling microscope to demonstrate that a single CuO_2 plane can form a stable and atomically ordered layer at the surface of Bi_2Sr_2CaCu_2O_{8+delta}. In contrast to previous studies on high-T_c surfaces, the CuO_2-terminated surface exhibits a strongly suppressed tunneling conductance at low voltages. We consider a number of different explanations for this phenomena and propose that it may be caused by how the orbital symmetry of the CuO_2 plane's electronic states affects the tunneling process.