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arXiv · 1505.06141

Interfacing transitions of different alkali atoms and telecom bands using one narrowband photon pair source

Gerhard Schunk·Ulrich Vogl·Dmitry V. Strekalov·Michael Förtsch·Florian Sedlmeir·Harald G. L. Schwefel·Manuela Göbelt·Silke Christiansen·Gerd Leuchs·Christoph Marquardt
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Abstract

Quantum information technology strongly relies on coupling of optical photons with narrowband quantum systems, such as quantum dots, color centers, and atomic systems. This coupling requires matching the optical wavelength and bandwidth to the desired system, which presents a considerable problem for most available sources of quantum light. Here we demonstrate coupling of alkali dipole transitions with a tunable source of photon pairs. Our source is based on spontaneous parametric down-conversion in a triply-resonant whispering-gallery mode resonator. For this, we have developed novel wavelength tuning mechanisms, which allow for a coarse tuning to either cesium or rubidium wavelength with subsequent continuous fine-tuning to the desired transition. As a demonstration of the functionality of the source, we performed a heralded single photon measurement of the atomic decay. We present a major advance in controlling the spontaneous down-conversion process, which makes our bright source of single photons now compatible with a plethora of narrow-band resonant systems.

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Gerhard Schunk, Ulrich Vogl, Dmitry V. Strekalov, Michael Förtsch, Florian Sedlmeir, Harald G. L. Schwefel, Manuela Göbelt, Silke Christiansen, Gerd Leuchs, Christoph Marquardt. 2015-10-01. Interfacing transitions of different alkali atoms and telecom bands using one narrowband photon pair source. https://doi.org/10.1364/optica.2.000773

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