Quantum circuits generating four-qubit maximally entangled states

TL;DR

This paper presents quantum circuits designed to generate four-qubit maximally entangled states, using CNOT gates on specific states within the local unitary orbit, and quantifies entanglement with the Cayley hyperdeterminant.

Contribution

It introduces a method to produce four-qubit maximally entangled states via specific quantum circuits and characterizes their entanglement using a mathematical monotone.

Findings

Quantum circuits can generate four-qubit maximally entangled states.

Entanglement is quantified using the Cayley hyperdeterminant.

Maximally entangled states are obtained from special LU orbit states.

Abstract

We describe quantum circuits generating four-qubit maximally entangled states, the amount of entanglement being quantified by using the absolute value of the Cayley hyperdeterminant as an entanglement monotone. More precisely, we show that this type of four-qubit entangled states can be obtained by the action of a family of CNOT circuits on some special states of the LU orbit of the state |0000 >.