Efficient quantum gates for individual nuclear spin qubits by indirect control
At a Glance
Section titled āAt a Glanceā| Metadata | Details |
|---|---|
| Publication Date | 2020-05-13 |
| Journal | Zenodo (CERN European Organization for Nuclear Research) |
| Authors | Swathi S. Hegde, Jingfu Zhang, Dieter Suter |
| Institutions | TU Dortmund University |
Abstract
Section titled āAbstractā<p>Hybrid quantum registers, such as electron-nuclear spin systems, have emerged as promising hard-<br>\nware for implementing quantum information and computing protocols in scalable systems. Neverthe-<br>\nless, the coherent control of such systems still faces challenges. Particularly, the lower gyromagnetic<br>\nratios of the nuclear spins cause them to respond slowly to control fields, resulting in gate times<br>\nthat are generally longer than the coherence time of the electron. Here, we demonstrate a scheme<br>\nfor circumventing this problem by indirect control: We apply a small number of short pulses only<br>\nto the electron and let the full system undergo free evolution under the hyperfine coupling between<br>\nthe pulses. Using this scheme, we realize robust quantum gates in an electron-nuclear spin system,<br>\nincluding a Hadamard gate on the nuclear spin and a controlled-NOT gate with the nuclear spin<br>\nas the target qubit. The durations of these gates are shorter than the electron coherence time, and<br>\nthus additional operations to extend the system coherence time are not needed. Our demonstration<br>\nserves as a proof of concept for achieving efficient coherent control of electron-nuclear spin systems,<br>\nsuch as NV centers in diamond. Our scheme is still applicable when the nuclear spins are only<br>\nweakly coupled to the electron.</p>