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تسجيل مستخدم جديدCoherent superconducting quantum pump
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We demonstrate non-adiabatic charge pumping utilizing a sequence of coherent oscillations between a superconducting island and two reservoirs. Our method, based on pulsed quantum state manipulations, allows to speedup charge pumping to a rate which is limited by the coupling between the island and the reservoirs given by the Josephson energy. Our experimental and theoretical studies also demonstrate that relaxation can be employed to reset the pump and avoid accumulation of errors due to non-ideal control pulses.
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Ten years ago, coherent oscillations between two quantum states of a superconducting circuit differing by the presence or absence of a single Cooper pair on a metallic island were observed for the first time. This result immediately stimulated the de
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We study adiabatic charge transfer in a superconducting Cooper pair pump, focusing on the influence of current measurement on coherence. We investigate the limit where the Josephson coupling energy $E_J$ between the various parts of the system is sma
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