Harty, Thomas

Date:  Wednesday, February 15, 2017
Time: 13:00
Place: ETH Zurich, Hönggerberg, HPF G 6
Host:  Jonathan Home

Microwave-driven quantum logic with trapped ions

Thomas Harty
University of Oxford, UK

Despite the fact that many ion qubits are based on transitions in the microwave regime, they are almost always manipulated using laser, rather than microwave radiation. This is because the long wavelength of free-space microwaves precludes strong qubit-qubit interactions or the production of localised fields for manipulating individual qubits. However, there are techniques [1][2], which can overcome this limitation and allow the advantages of microwave technology to be harnessed in trapped ion experiments.

In this talk, I describe the ongoing research project at Oxford to use near-field microwaves to drive quantum logic gates. I present our work so far, including recent experiments [3] using a novel dynamically decoupled Molmer-Sorensen gate mechanism to demonstrate a microwave-driven gate with 99.7% fidelity -- close to the state of the art for laser gates. I discuss some potential challenges and opportunities for scaling up microwave quantum logic systems.

[1] F. Mintert and C. Wunderlich, Phys. Rev. Lett. 87, 257904 (2001) [2] C. Ospelkaus et al., Phys. Rev. Lett. 101, 090502 (2008) [3] T. P. Harty, et al., Phys. Rev. Lett. 117, 140501 (2016)