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تسجيل مستخدم جديدCoherent electron-spin-resonance manipulation of three individual spins in a triple quantum dot
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Quantum dot arrays provide a promising platform for quantum information processing. For universal quantum simulation and computation, one central issue is to demonstrate the exhaustive controllability of quantum states. Here, we report the addressable manipulation of three single electron spins in a triple quantum dot using a technique combining electron-spin-resonance and a micro-magnet. The micro-magnet makes the local Zeeman field difference between neighboring spins much larger than the nuclear field fluctuation, which ensures the addressable driving of electron-spin-resonance by shifting the resonance condition for each spin. We observe distinct coherent Rabi oscillations for three spins in a semiconductor triple quantum dot with up to 25 MHz spin rotation frequencies. This individual manipulation over three spins enables us to arbitrarily change the magnetic spin quantum number of the three spin system, and thus to operate a triple-dot device as a three-qubit system in combination with the existing technique of exchange operations among three spins.
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Spin qubits involving individual spins in single quantum dots or coupled spins in double quantum dots have emerged as potential building blocks for quantum information processing applications. It has been suggested that triple quantum dots may provid
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A fundamental goal in the manipulation of quantum systems is the achievement of many coherent oscillations within the characteristic dephasing time T2*[1]. Most manipulations of electron spins in quantum dots have focused on the construction and cont
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Coherent interactions between spins in quantum dots are a key requirement for quantum gates. We have performed pump-probe experiments in which pulsed lasers emitting at different photon energies manipulate two distinct subsets of electron spins withi
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Electron spins in semiconductor quantum dots are good candidates of quantum bits for quantum information processing. Basic operations of the qubit have been realized in recent years: initialization, manipulation of single spins, two qubit entanglemen
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