Universal gates for transforming multipartite entangled Dicke states

TL;DR

This paper identifies the minimal qubit access needed to transform Dicke states into other Dicke states and introduces universal optimal gates for such transformations, impacting quantum information processing.

Contribution

It introduces universal optimal gates for transforming Dicke states with minimal qubit access, a novel approach compared to other entangled states.

Findings

Minimal qubit access needed for Dicke state transformation

Construction of universal optimal gates for Dicke states

Implications for quantum state generation in physical systems

Abstract

We determine the minimal number of qubits that it is necessary to have access to in order to transform Dicke states into other Dicke states. In general, the number of qubits in Dicke states cannot be increased via transformation gates by accessing only a single qubit, in direct contrast to other multipartite entangled states such as GHZ, W and cluster states. We construct a universal optimal gate which adds spin-up qubits or spin-down qubits to any Dicke state by minimal access. We also show the existence of a universal gate which transforms any size of Dicke state as long as it has access to at least the required number of qubits. Our results have important consequences for the generation of Dicke states in physical systems such as ion traps, all-optical setups and cavity-QED settings where they can be used for a variety of quantum information processing tasks.