Usefulness of Multiqubit W-type States in Quantum Information Processing Task

TL;DR

This paper investigates the potential of multiqubit W-type states as resources for quantum information tasks, highlighting their advantages and limitations in practical implementations and protocols like dense coding.

Contribution

It generalizes four-qubit W-type states and demonstrates their utility in deterministic quantum information processing and bipartite entanglement, comparing their effectiveness to three-qubit states.

Findings

Four-qubit W states outperform three-qubit states for certain tasks.

W states enable deterministic dense coding of two classical bits.

Experimental limitations affect the practical utility of multiqubit W states.

Abstract

We analyze the efficacy of multiqubit W-type states as resources for quantum information. For this, we identify and generalize four-qubit W-type states. Our results show that the states can be used as resources for deterministic quantum information processing. The utility of results, however, is limited by the availability of experimental setups to perform and distinguish multiqubit measurements. We, therefore, emphasize on another protocol where two users want to establish an optimal bipartite entanglement using the partially entangled W-type states. We found that for such practical purposes, four-qubit W states can be a better resource in comparison to three-qubit W-type states. For dense coding protocol, our states can be used deterministically to send two bits of classical message by locally manipulating a single qubit.