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arXiv · 1501.06294

Quantum logic gates from time-dependent global magnetic field in a system with constant exchange

A. V. Nenashev·A. F. Zinovieva·A. V. Dvurechenskii·A. Yu. Gornov·T. S. Zarodnyuk
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Abstract

We propose a method for implementation of an universal set of one- and two-quantum-bit gates for quantum computation in the system of two coupled electrons with constant non-diagonal exchange interaction. Suppression of the exchange interaction is offered to implement by all-the-time repetition of single spin rotations. Small g-factor difference of electrons allows to address qubits and to avoid strong magnetic field pulses. It is shown by means of numerical experiments that for implementation of one- and two-qubit operations it is sufficient to change the amplitude of the magnetic field within a few Gauss, introducing in a resonance one and then the other electron. To find the evolution of the two-qubit system, we use the algorithms of the optimal control theory.

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A. V. Nenashev, A. F. Zinovieva, A. V. Dvurechenskii, A. Yu. Gornov, T. S. Zarodnyuk. 2015-01-26. Quantum logic gates from time-dependent global magnetic field in a system with constant exchange. https://doi.org/10.1063/1.4915347

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