• Corpus ID: 248811380

Multi-state Swap Test Algorithm

  title={Multi-state Swap Test Algorithm},
  author={Wen Liu and Han-Wen Yin and Zhi-Rao Wang and Wenbing Fan},
. Estimating the overlap between two states is an important task with several applications in quantum information. However, the typical swap test circuit can only measure a sole pair of quantum states at a time. In this study we designed a recursive quantum circuit to measure overlaps of multiple quantum states | φ 1 ...φ n (cid:105) concurrently with O ( n log n ) controlled-swap (CSWAP) gates and O (log n ) ancillary qubits. This circuit enables us to get all pairwise overlaps among input…