Double-dangling-bond defects and band bending at the GaAs (110) surface

We note that contact-potential measurements which have shown band bending at the nonpolar GaAs surface can be interpreted with a simple model for cleavage defects at the surface. We find that defects with two dangling bonds at the surface produce both filled and empty defect states in the gap. This result then supports experimental work indicating that band bending at GaAs(110) is defect related.