A General Method for Selecting Quantum Channel for Bidirectional Controlled State Teleportation and Other Schemes of Controlled Quantum Communication

TL;DR

This paper introduces a universal method for selecting multi-qubit quantum channels suitable for various controlled quantum communication protocols, expanding beyond existing specific channels and enabling new applications.

Contribution

It presents a general approach to identify quantum channels for BCST and related tasks, unifying and extending previous protocols with a broader set of channels.

Findings

Existing BCST channels are a small subset of the proposed set.

All these channels are also applicable for controlled bidirectional remote state preparation.

The method can be extended to other controlled quantum communication schemes.

Abstract

Recently, a large number of protocols for bidirectional controlled state teleportation (BCST) have been proposed using $n$-qubit entangled states ($n\in\{5,6,7\}$) as quantum channel. Here, we propose a general method of selecting multi-qubit $(n>4)$ quantum channels suitable for BCST and show that all the channels used in the existing protocols of BCST can be obtained using the proposed method. Further, it is shown that the quantum channels used in the existing protocols of BCST forms only a negligibly small subset of the set of all the quantum channels that can be constructed using the proposed method to implement BCST. It is also noted that all these quantum channels are also suitable for controlled bidirectional remote state preparation (CBRSP). Following the same logic, methods for selecting quantum channels for other controlled quantum communication tasks, such as controlled bidirectional joint remote state preparation (CJBRSP) and controlled quantum dialogue, are also provided.