It was recalled that scanning tunnelling microscopy had recently been used to study bulk As antisite defects in this material. Extensive theoretical calculations of such defects in the vicinity of a (110) surface were reported here. It was found that the defects exhibited distinct properties, depending upon whether they were 4-fold or 3-fold coordinated. The nature of the satellite peaks which were observed in experiments was elucidated. The conditions under which scanning tunnelling microscopic observations were expected to reflect the properties of the bulk defect were also predicted.

R.B.Capaz, K.Cho, J.D.Joannopoulos: Physical Review Letters, 1995, 75[9], 1811-4