Hits:

Indexed by:期刊论文

Date of Publication:2014-02-07

Journal:PHYSICS LETTERS A

Included Journals:SCIE、Scopus

Volume:378

Issue:9

Page Number:699-704

ISSN No.:0375-9601

Key Words:Lyapunov control; Quantum gate; Local equivalence class; CNOT gate

Abstract:We propose a Lyapunov control design to achieve specific (or a family of) unitary time-evolution operators, i.e., quantum gates in the Schrodinger picture by tracking control. Two examples are presented. In the first, we illustrate how to realize the Hadamard gate in a single-qubit system, while in the second, the controlled-NOT (CNOT) gate is implemented in two-qubit systems with the Ising and Heisenberg interactions. Furthermore, we demonstrate that the control can drive the time-evolution operator into the local equivalence class of the CNOT gate and the operator keeps in this class forever with the existence of Ising coupling. (C) 2014 Elsevier B.V. All rights reserved.