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arXiv · 0708.1308

Universal Dephasing Control During Quantum Computation

Goren Gordon·Gershon Kurizki
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Abstract

Dephasing is a ubiquitous phenomenon that leads to the loss of coherence in quantum systems and the corruption of quantum information. We present a universal dynamical control approach to combat dephasing during all stages of quantum computation, namely, storage, single- and two-qubit operators. We show that (a) tailoring multi-frequency gate pulses to the dephasing dynamics can increase fidelity; (b) cross-dephasing, introduced by entanglement, can be eliminated by appropriate control fields; (c) counter-intuitively and contrary to previous schemes, one can increase the gate duration, while simultaneously increasing the total gate fidelity.

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Goren Gordon, Gershon Kurizki. 2007-08-09. Universal Dephasing Control During Quantum Computation. https://doi.org/10.1103/physreva.76.042310

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