## Deterministic local doubling of W states

OPTICA, vol.33, pp.2313-2319, 2016 (SCI-Expanded)

• Publication Type: Article / Article
• Volume: 33
• Publication Date: 2016
• Journal Name: OPTICA
• Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
• Page Numbers: pp.2313-2319
• Istanbul University Affiliated: Yes

#### Abstract

In large quantum systems, multipartite entanglement can be found in many inequivalent classes. Preparing states of arbitrary size in different classes is important for performing a wide range of quantum protocols. W" role="presentation" >$W$ states, in particular, constitute a class with a variety of quantum networking protocols. However, all known schemes for preparing polarization encoded photonic W" role="presentation" >$W$ states are probabilistic, with resource requirements increasing at least sub-exponentially. We propose a deterministic scheme for preparing W" role="presentation" >$W$ states of size of any power of 2, which requires no prior entanglement and can be performed locally. We introduce an all-optical setup that can efficiently double the size of W" role="presentation" >$W$ states of arbitrary size. Our scheme advances the use of W" role="presentation" >$W$ states in real-world quantum networks and could be extended to other physical systems.