Linear Optical Schemes to Postselect High-Dimensional Dicke States

TL;DR

This paper introduces linear optical schemes for efficiently postselecting high-dimensional symmetric Dicke states, enhancing success probabilities with ancillary photons for quantum communication and computing.

Contribution

The paper presents new linear optical interference schemes, including those with ancillary photons, to improve postselection success rates of symmetric qudit Dicke states.

Findings

Ancillary photon schemes surpass success probability bounds of non-ancillary schemes.

Multiple viable linear optical approaches for Dicke state postselection are demonstrated.

Schemes are applicable to a wide range of quantum communication and computing tasks.

Abstract

Multipartite entanglement is an essential quantum resource for various distributed quantum applications. One promising method for preparing multipartite entanglement is to interfere independent photons at linear optical interference setups. While heralding the successful interference and thereby the state generation is often costly, postselecting entangled states provides an achievable alternative in this framework. We introduce a family of interference schemes for postselecting symmetric qudit Dicke states, useful resources in quantum communication and variational quantum computing. We present schemes with and without ancillary photons and show that using ancillary photons can exceed the upper bound on the success probability of schemes without ancillary photons. Our results accommodate a wide range of linear optical schemes, providing multiple viable approaches for postselecting Dicke states.