Fusing multiple W states simultaneously with a Fredkin gate

ÖZAYDIN F., Bugu S., Yesilyurt C., ALTINTAŞ A. A., Tame M., Ozdemir S. K.

PHYSICAL REVIEW A, vol.89, no.4, 2014 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 89 Issue: 4
  • Publication Date: 2014
  • Doi Number: 10.1103/physreva.89.042311
  • Journal Name: PHYSICAL REVIEW A
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Istanbul University Affiliated: Yes

Abstract

We propose an optical scheme to prepare large-scale entangled networks of W states. The scheme works by simultaneously fusing three polarization-encoded W states of arbitrary size via accessing only one qubit of each W state. It is composed of a Fredkin gate (controlled-swap gate), two fusion gates [as proposed in S. K. Ozdemir et al., New J. Phys. 13, 103003 (2011)], and an H-polarized ancilla photon. Starting with three n-qubit W states, the scheme prepares a new W state with 3(n - 1) qubits after postselection if both fusion gates operate successfully, i.e., a fourfold coincidence at the detectors. The proposed scheme reduces the cost of creating arbitrarily large W states considerably when compared to previously reported schemes.