Decoherence-protected quantum gates for a hybrid solid-state spin register

التفاصيل البيبلوغرافية
العنوان: Decoherence-protected quantum gates for a hybrid solid-state spin register
المؤلفون: van der Sar, T., Wang, Z. H., Blok, M. S., Bernien, H., Taminiau, T. H., Toyli, D. M., Lidar, D. A., Awschalom, D. D., Hanson, R., Dobrovitski, V. V.
المصدر: Nature 484, 82-86 (2012)
سنة النشر: 2012
المجموعة: Condensed Matter
Quantum Physics
مصطلحات موضوعية: Condensed Matter - Mesoscale and Nanoscale Physics, Quantum Physics
الوصف: Protecting the dynamics of coupled quantum systems from decoherence by the environment is a key challenge for solid-state quantum information processing. An idle qubit can be efficiently insulated from the outside world via dynamical decoupling, as has recently been demonstrated for individual solid-state qubits. However, protection of qubit coherence during a multi-qubit gate poses a non-trivial problem: in general the decoupling disrupts the inter-qubit dynamics, and hence conflicts with gate operation. This problem is particularly salient for hybrid systems, wherein different types of qubits evolve and decohere at vastly different rates. Here we present the integration of dynamical decoupling into quantum gates for a paradigmatic hybrid system, the electron-nuclear spin register. Our design harnesses the internal resonance in the coupled-spin system to resolve the conflict between gate operation and decoupling. We experimentally demonstrate these gates on a two-qubit register in diamond operating at room temperature. Quantum tomography reveals that the qubits involved in the gate operation are protected as accurately as idle qubits. We further illustrate the power of our design by executing Grover's quantum search algorithm, achieving fidelities above 90% even though the execution time exceeds the electron spin dephasing time by two orders of magnitude. Our results directly enable decoherence-protected interface gates between different types of promising solid-state qubits. Ultimately, quantum gates with integrated decoupling may enable reaching the accuracy threshold for fault-tolerant quantum information processing with solid-state devices.
Comment: This is original submitted version of the paper. The revised and finalized version is in print, and is subjected to the embargo and other editorial restrictions of the Nature journal
نوع الوثيقة: Working Paper
DOI: 10.1038/nature10900
URL الوصول: http://arxiv.org/abs/1202.4379
رقم الأكسشن: edsarx.1202.4379
قاعدة البيانات: arXiv