Open AccessThe phonon effect of qubit in quantum ring
Author(s) -
Fushi Jiang,
Cui-Lan Zhao
Publication year - 2009
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.58.6786
Subject(s) - physics , flux qubit , charge qubit , qubit , phase qubit , excited state , coherence (philosophical gambling strategy) , electron , phonon , quantum mechanics , ground state , quantum , radius , ring (chemistry) , eigenfunction , condensed matter physics , atomic physics , chemistry , eigenvalues and eigenvectors , organic chemistry , computer security , computer science
Under the condition of electron-LO photon strong coupling, the eigenfunction and the eigenenergy of the ground state and the first excited state of the electron in quantum ring, are obtained by solving precisely the Schrdinger equation. A qubit is formed by overlaying both the ground state and the first excited state of the electron-LO phonon system.Numerical calculations indicate that the distribution of the probability density of electrons in quantum oscillates periodically with time and angle coordinate. The oscillating period decreases with the increase of the electron-LO phonon coupling strength, which shows that the existence of phonon can reduce the coherence of qubit, and that the oscillating period increases with the increasing inneror outer radius of quantum ring. Therefore, the coherence of qubit can be improved by choosing proper size of quantum ring.