Fusion ofW-like states in optical system
Ke Li, Ming Yang, Qing Yang, Zhuo‐Liang Cao · Laser Physics · 2016
An effective scheme is proposed for preparing large-scale maximally entangled W states by fusing arbitrary-size polarization entangled W or W -like states via polarization-dependent beam splitter (PDBS). In our scheme, W m + n −1 state can be generated from an n -qubit W state and an m -qubit W state, and W m + n + t −2 state can be generated from W m , W n and W t states. The fusion process can start with Bell states too. Because PDBS has selective transmission rates for different polarization states, our fusion has a distinct property, i.e. a large-scale maximally entangled W state can be generated by fusing small-size W -like states, and the cost analyses indicate that our fusion scheme is more efficient than the previous one in fusing W -like states. In addition, there is no need for any controlled quantum gate and any ancillary photon in our scheme, so it is simple and feasible.