On entanglement in the formalism of quantum circuits

Boeva A.V., Klinskikh A.F.

Voronezh State University, Russia

Quantum entanglement is one of the amazing and mysterious phenomena of quantum physics. It is a correlation of quantum systems, in which changes occurring in one system instantly affect the other. Interest in the study and application of quantum entanglement has increased significantly in recent decades [1]. The paper proposes quantum schemes for generating states with a given degree of entanglement for multi-qubit systems and an algorithm for analyzing their characteristics.

Each scheme corresponds to a unitary operator, the action of which determines the change in the state of the system.

The density matrices of the system and the lowest qubit are given by the state vector at the output of the circuit and the result of finding a partial trace over the remaining qubits of the system.

By feeding an un-entangled state to the input of the circuit, using the gate U, it is possible to change the amplitudes of the probabilities of qubits, thereby affecting the entanglement of the system.


1. Valiev, K. A. Quantum computers and quantum computing // Successes of Physical sciences. - 2005. — Vol. 175, No. 31. — pp. 3-39.


© 2004 Designed by Lyceum of Informational Technologies №1533