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IEEE Information Technology, Networking, Electronic and Automation Control Conference (ITNEC)

Preparation of the entanglement states by realizing the Hadamard and CNOT quantum gates

Nourallah Ghaeminezhad, Shuang Cong

Published Mar 1, 2019• 1 citation
Publisher

Abstract

The preparation of the maximum entangled states, i.e., the Bell states is studied in this paper. The Cartan decomposition and the Lyapunov control methods are used to design the control laws for some operations in realizing the Hadamard and CNOT gates to prepare the Bell states. The numerical simulation experiments show that for some proper control parameters in the designed control laws, the Hadamard and CNOT gates are realized and the stable Bell states are prepared in a short time.

DOI
10.1109/itnec.2019.8729503

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Bell states are the maximally entangled states in two-qubit quantum systems, and play a significant role in quantum computation and quantum communication. Feedback control of stochastic quantum systems usually suffers from time-delay problems caused by the computation time for filter states and the control input. This paper addresses the preparation of Bell states in two-qubit systems with a constant delay time. A Lyapunov method is used to design a switching control law and a constant is introduced to compensate for the computation time of the estimated states and the feedback control input, thereby stabilizing the target Bell state globally. Numerical results show the effectiveness of the proposed control law.
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