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arXiv · 1510.04098

Optimizing electrically controlled echo sequences for the exchange-only qubit

Niklas Rohling·Guido Burkard
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Abstract

Recently, West and Fong [New J. Phys. 14, 083002 (2012)] introduced an echo scheme for an exchange-only qubit, which relies entirely on the exchange-interaction. Here, we compare two different exchange-based sequences and two optimization strategies, Uhrig dynamical decoupling (UDD) and optimized filter function dynamical decoupling (OFDD), which were introduced for a single-spin qubit and are applied in this paper to the three-spin exchange-only qubit. The calculation shows that the adaption of the optimization concepts can be achieved by straight-forward calculation. We consider two types of noise spectra, Lorentzian and Ohmic noise. For both spectra, the results reveal a slight dependence of the performance on the choice of the echo sequence.

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Niklas Rohling, Guido Burkard. 2015-10-14. Optimizing electrically controlled echo sequences for the exchange-only qubit. https://doi.org/10.1103/physrevb.93.205434

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