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arXiv · 1712.08158

Frequency Feedback for Two-Photon Interference from Separate Quantum Dots

Michael Zopf·Tobias Macha·Robert Keil·Eduardo Uruñuela·Yan Chen·Wolfgang Alt·Lothar Ratschbacher·Fei Ding·Dieter Meschede·Oliver G. Schmidt
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Abstract

We employ active feedback to stabilize the frequency of single photons emitted by two separate quantum dots to an atomic standard. The transmission of a single, rubidium-based Faraday filter serves as the error signal for frequency stabilization to less than 1.5% of the emission linewidth. Long-term stability is demonstrated by Hong-Ou-Mandel interference between photons from the two quantum dots. The observed visibility of $V_{\mathrm{lock}}=(41 \pm 5)$% is limited only by internal dephasing of the dots. Our approach facilitates quantum networks with indistinguishable photons from distributed emitters.

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Michael Zopf, Tobias Macha, Robert Keil, Eduardo Uruñuela, Yan Chen, Wolfgang Alt, Lothar Ratschbacher, Fei Ding, Dieter Meschede, Oliver G. Schmidt. 2017-12-21. Frequency Feedback for Two-Photon Interference from Separate Quantum Dots. https://doi.org/10.1103/physrevb.98.161302

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