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arXiv · 1004.2758

Proposal of a full Bell state analyzer for spin qubits in a double quantum dot

Nobuhiko Yokoshi·Hiroshi Imamura·Hideo Kosaka
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Abstract

We propose a scheme for full Bell state measurement of spin qubits in a double quantum dot. Our scheme consists of Pauli spin-blockade measurements and biaxial electron-spin resonance. In order to eliminate the average of the Zeeman fields, the double quantum dot is designed so that the Land\'e g-factors of first and second dots satisfy g1=g2 with the use of g-factor engineering. Thus, we can swap one of the three spin-triplet states for the spin-singlet state without disturbing the other states. Our study shows that the sequential spin-to-charge conversions enable us to implement the full Bell state measurement of electron-spin qubits.

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Nobuhiko Yokoshi, Hiroshi Imamura, Hideo Kosaka. 2010-04-16. Proposal of a full Bell state analyzer for spin qubits in a double quantum dot. https://doi.org/10.1103/physrevb.81.161305

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