Enhancing the W -state quantum-network-fusion process with a single Fredkin gate
Sinan Bugu, Can Yesilyurt, Fatih Özaydin · Physical Review A · 2013
Integrating a single Fredkin (controlled swap) gate to the previously introduced $W$ state fusion mechanism [Ozdemir et al., New J. Phys. 13, 103003 (2011)] and using an ancillary photon, we increase the size of the fused $W$ states and essentially, we improve the success probability of the fusion process in a promising way for a possible deterministic $W$-state fusion mechanism. Besides fusing arbitrary size $W$ states, our setup can also fuse Bell states to create $W$ states with a success probability $3/4$ which is much higher than the previous works. Therefore using only this setup, it is now possible to start with Bell pairs to create and expand arbitrary size $W$ states. Since a higher probability of success implies a lower cost of resource in terms of the number of the states spent to achieve a target size, our setup gives rise to more cost-efficient scenarios.