Templates for positive and negative control Toffoli networks

Abstract

Circuit realizations obtained from existing logic synthesis approaches may not be optimal and thus one commonly applies post-synthesis optimization techniques to get better realization of the circuits. This thesis proposes two new templates (templates 4 and 7) for positive and negative control Toffoli gates as well as proposing algorithms for post synthesis optimization of reversible positive and negative control Toffoli networks by utilizing the set of templates. When applying the templates to circuits generated by the improved shared cube synthesis approach [23] a reduction in quantum cost was achieved for 86 of the 110 circuits. On average a 21.34% reduction in quantum cost was achieved, and in some cases up to 53.58% reduction was obtained.