Ramsey fringes in an electric-field-tunable quantum dot system.
We report on Ramsey fringes measured in a single InGaAs/GaAs quantum dot two-level system. We are able to control the transition energy of the system by Stark effect tuning. In combination with double pulse excitation this allows for a voltage controlled preparation of the phase and the occupancy of the two-level system. For long pulse delay times we observe extremely narrow fringes with spectral width below the homogeneous linewidth of the system. Implications on quantum information processing are discussed.
Stufler
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S
Universität Paderborn, Warburger Strasse 100, D-33098 Paderborn, Germany. stufler@physik.upb.de
Ester
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Zrenner
A
A
Bichler
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