Qubit transformations on Rashba ring with periodic potential. (18th August 2020)

• Record Type: Journal Article
• Authors: Kregar, Ambrož; Ramšak, Anton
• Is Part Of: New journal of physics. Volume 22:Number 8(2020:Aug.)
• Publication Date: 2020-08-18
• Subjects: Rashba coupling -- qubit transformation -- quatum ring -- periodic potential; Physics -- Periodicals; Physics; Periodicals; 530.05
• DOI: 10.1088/1367-2630/aba462
• Languages: English
• ISSNs: 1367-2630

Abstract

Abstract: A spin-qubit transformation protocol is proposed for an electron in a mesoscopic quantum ring with tunable Rashba interaction controlled by the external electric field. The dynamics of an electron driven around the ring by a series of Landau–Zenner-like transitions between a finite number of local voltage gates is determined analytically. General single-qubit transformations are demonstrated to be feasible in a dynamical basis of localized pseudo-spin states. It is also demonstrated that by the use of suitable protocols based on changes of the Rashba interaction full Bloch sphere can be covered. The challenges of a possible realization of the proposed system in semiconductor heterostructures are discussed.