Dephasing of Coupled Spin Qubit System during Gate Operations Due to Background Charge Fluctuations

2004/10/04 by Toshifumi Itakura
Computer Science · Physics and Astronomy · #Quantum Computing Algorithms and Architecture #Quantum and electron transport phenomena #Quantum-Dot Cellular Automata #cond-mat.mes-hall #cond-mat.mtrl-sci #quant-ph

paper · pdf · doi:10.1143/jpsj.73.3266

10 pages, 7 figure. to be published

arxiv created 2004/10/04 · openalex publication_date 2004/12/15 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28

Abstract

It has been proposed that a quantum computer can be constructed based on electron spins in quantum dots or based on a superconducting nanocircuit. During two-qubit operations, the fluctuation of the coupling parameters is a critical factor. One source of such fluctuation is the stirring of the background charges. We focused on the influence of this fluctuation on a coupled spin qubit system. The induced fluctuation in exchange coupling changes the amount of entanglement, fidelity, and purity. In our previous study, the background charge fluctuations were found to be an important channel of dephasing for a single Josephson qubit.

Citations

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