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arXiv · 0809.2946

CdSe quantum dots in ZnSe nanowires as efficient source for single photons up to 220 K

Thomas Aichele·Adrien Tribu·Gregory Sallen·Juanita Bocquel·Edith Bellet-Amalric·Catherine Bougerol·Jean-Philippe Poizat·Kuntheak Kheng·Régis André·Serge Tatarenko
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Abstract

ZnSe nanowire heterostructures were grown by molecular beam epitaxy in the vapour-liquid-solid growth mode assisted by gold catalysts. Size, shape and crystal structure are found to strongly depend on the growth conditions. Both, zinc-blende and wurtzite crystal structures are observed using transmission electron microscopy. At low growth temperature, cone-shaped nano-needles are formed. For higher growth temperature, the nanowires are uniform and have a high aspect ratio with sizes of 1-2 $μ$m in length and 20-50 nm in width as observed by scanning electron microscopy. Growing a nanowire on top of a nano-needle allows us to obtain very narrow nanorods with a diameter less than 10 nm and a low density of stacking fault defects. These results allow us the insertion of CdSe quantum dots in a ZnSe nanowire. An effcient photon anti-bunching was observed up to 220 K, demonstrating a high-temperature single-photon source.

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Thomas Aichele, Adrien Tribu, Gregory Sallen, Juanita Bocquel, Edith Bellet-Amalric, Catherine Bougerol, Jean-Philippe Poizat, Kuntheak Kheng, Régis André, Serge Tatarenko. 2008-09-17. CdSe quantum dots in ZnSe nanowires as efficient source for single photons up to 220 K. https://doi.org/10.1016/j.jcrysgro.2008.10.103

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