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تسجيل مستخدم جديدMicro-magnets for coherent control of spin-charge qubit in lateral quantum dots
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A lateral quantum dot design for coherent electrical manipulation of a two-level spin-charge system is presented. Two micron-size permanent magnets integrated to high-frequency electrodes produce a static slanting magnetic field suitable for voltage controlled single qubit gate operations. Stray field deviation from the slanting form is taken into account in the Hamiltonian describing the two-level system, which involves hybridization of a single electron spin to the quantum dots orbitals. Operation speed and gate fidelity are related to device parameters. Sub 100 ns $pi$ pulse duration can be achieved with lattice fluctuations coherence time of 4 ms for GaAs.
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