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تسجيل مستخدم جديدA Tuneable Few Electron Triple Quantum Dot
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In this paper we report on a tuneable few electron lateral triple quantum dot design. The quantum dot potentials are arranged in series. The device is aimed at studies of triple quantum dot properties where knowing the exact number of electrons is important as well as quantum information applications involving electron spin qubits. We demonstrate tuning strategies for achieving required resonant conditions such as quadruple points where all three quantum dots are on resonance. We find that in such a device resonant conditions at specific configurations are accompanied by novel charge transfer behaviour.
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Quantum dots are considered building blocks for future quantum information circuits. We present here experimental results on a quantum dot circuit consisting of three quantum dots with controlled electron numbers down to one per dot and tunable coupl
ing. We experimentally map out for the first time the stability diagram of the triatomic system and reveal the existence of quadruple points, a signature of the three dots being in resonance. In their vicinity we observe a surprising effect, a cloning of charge transfer transitions related to charge and spin reconfigurations. The experimental results are reproduced by equivalent circuit analysis and Hubbard models.
A few electron double electrostatic lateral quantum dot can be transformed into a few electron triple quantum dot by applying a different combination of gate voltages. Quadruple points have been achieved at which all three dots are simultaneously on
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