Universal quantum Controlled-NOT gate

TL;DR

This paper explores an optimal universal quantum C-NOT gate that operates on unknown qubit states from a great circle on the Bloch sphere, highlighting its relation to equatorial quantum cloning machines and potential applications.

Contribution

It introduces a universal C-NOT gate optimized for unknown qubit states and reveals its analogy with equatorial quantum cloning machines.

Findings

The universal C-NOT gate performs specific operations on unknown qubits.

It exhibits a deep analogy with equatorial quantum cloning machines.

Potential applications of the universal C-NOT gate are discussed.

Abstract

An investigation of an optimal universal unitary Controlled-NOT gate that performs a specific operation on two unknown states of qubits taken from a great circle of the Bloch sphere is presented. The deep analogy between the optimal universal C-NOT gate and the `equatorial' quantum cloning machine (QCM) is shown. In addition, possible applications of the universal C-NOT gate are briefly discussed.