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arXiv · 1102.5372

Low-temperature tapered-fiber probing of diamond NV ensembles coupled to GaP microcavities

K. -M. C. Fu·P. E. Barclay·C. Santori·A. Faraon·R. G. Beausoleil
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Abstract

In this work we present a platform for testing the device performance of a cavity-emitter system, using an ensemble of emitters and a tapered optical fiber. This method provides high-contrast spectra of the cavity modes, selective detection of emitters coupled to the cavity, and an estimate of the device performance in the single- emitter case. Using nitrogen-vacancy (NV) centers in diamond and a GaP optical microcavity, we are able to tune the cavity onto the NV resonance at 10 K, couple the cavity-coupled emission to a tapered fiber, and measure the fiber-coupled NV spontaneous emission decay. Theoretically we show that the fiber-coupled average Purcell factor is 2-3 times greater than that of free-space collection; although due to ensemble averaging it is still a factor of 3 less than the Purcell factor of a single, ideally placed center.

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BibTeXRIS

K. -M. C. Fu, P. E. Barclay, C. Santori, A. Faraon, R. G. Beausoleil. 2011-02-25. Low-temperature tapered-fiber probing of diamond NV ensembles coupled to GaP microcavities. https://doi.org/10.1088/1367-2630/13/5/055023

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