Heralded Linear Optical Generation of Dicke States

TL;DR

This paper introduces a resource-efficient linear-optical heralded method for generating arbitrary Dicke states, overcoming previous structural complexities and enabling practical quantum information applications.

Contribution

The authors develop a novel linear-optical scheme using the linear quantum graph framework to heraldedly generate Dicke states with improved efficiency.

Findings

Successfully maps scheme design to graph-finding problem

Overcomes structural complexity of previous approaches

Provides a practical pathway for heralded Dicke state preparation

Abstract

Entanglement is a fundamental feature of quantum mechanics and a key resource for quantum information processing. Among multipartite entangled states, Dicke states $|D_n^k\rangle$ are distinguished by their permutation symmetry, which provides robustness against particle loss and enables applications for quantum communication and computation. Although Dicke states have been realized in various platforms, most optical implementations rely on postselection, which destroys the state upon detection and prevents its further use. A heralded optical scheme is therefore highly desirable. Here, we present a linear-optical heralded scheme for generating arbitrary Dicke states $|D_n^k\rangle$ with $3n+k$ photons through the framework of the linear quantum graph (LQG) picture. By mapping the scheme design into the graph-finding problem, and exploiting the permutation symmetry of Dicke states, we overcome the structural complexity that has hindered previous approaches. Our results provide a resource-efficient pathway toward practical heralded preparation of Dicke states for quantum technologies.