Quantum Coherence Measures for Quantum Switch

TL;DR

This paper proposes using a coherence measure to analyze and verify the operation of a quantum switch, especially under noise and decoherence, facilitating future quantum network implementations.

Contribution

It introduces a coherence measure tailored for quantum switches and demonstrates how to estimate it via a quantum circuit to assess switch performance.

Findings

Coherence measure effectively describes quantum switch operation.

Quantum circuit can estimate the coherence measure.

Analysis includes noise and decoherence effects.

Abstract

We suppose that a structure working as a quantum switch will be a significant element of future networks realizing transmissions of quantum information. In this chapter we analyze a process of switch's operating -- especially in systems with a noise presence. The noise is caused by a phenomenon of quantum decoherence, i.e. distorting of quantum states because of an environmental influence, and also by some imperfections of quantum gates' implementation. In the face of mentioned problems, the possibility of tracing the switch's behavior during its operating seems very important. To realize that we propose to utilize a Coherence measure which, as we present in this chapter, is sufficient to describe operating of the quantum switch and to verify correctness of this process. It should be also stressed that the value of Coherence measure may be estimated by a quantum circuit, designed especially for this purpose.