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arXiv · 1804.00713

Controllable photonic time-bin qubits from a quantum dot

J. P. Lee·L. M. Wells·B. Villa·S. Kalliakos·R. M. Stevenson·D. J. P. Ellis·I. Farrer·D. A. Ritchie·A. J. Bennett·A. J. Shields
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Abstract

Photonic time bin qubits are well suited to transmission via optical fibres and waveguide circuits. The states take the form $\frac{1}{\sqrt{2}}(\alpha \ket{0} + e^{i\phi}\beta \ket{1})$, with $\ket{0}$ and $\ket{1}$ referring to the early and late time bin respectively. By controlling the phase of a laser driving a spin-flip Raman transition in a single-hole-charged InAs quantum dot we demonstrate complete control over the phase, $\phi$. We show that this photon generation process can be performed deterministically, with only a moderate loss in coherence. Finally, we encode different qubits in different energies of the Raman scattered light, demonstrating wavelength division multiplexing at the single photon level.

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J. P. Lee, L. M. Wells, B. Villa, S. Kalliakos, R. M. Stevenson, D. J. P. Ellis, I. Farrer, D. A. Ritchie, A. J. Bennett, A. J. Shields. 2018-04-02. Controllable photonic time-bin qubits from a quantum dot. https://doi.org/10.1103/physrevx.8.021078

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