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arXiv · 0906.4181

Photonic crystal nanocavity laser with a single quantum dot gain

Masahiro Nomura·Naoto Kumagai·Satoshi Iwamoto·Yasutomo Ota·Yasuhiko Arakawa
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Abstract

We demonstrate a photonic crystal nanocavity laser essentially driven by a self-assembled InAs/GaAs single quantum dot gain. The investigated nanocavities contain only 0.4 quantum dots on an average; an ultra-low density quantum dot sample (1.5 x 108 cm-2) is used so that a single quantum dot can be isolated from the surrounding quantum dots. Laser oscillation begins at a pump power of 42 nW under resonant condition, while the far-detuning conditions require ~145 nW for lasing. This spectral detuning dependence of laser threshold indicates substantial contribution of the single quantum dot to the total gain. Moreover, photon correlation measurements show a distinct transition from anti-bunching to Poissonian via bunching with the increase of the excitation power, which is also an evidence of laser oscillation with the single quantum dot.

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Masahiro Nomura, Naoto Kumagai, Satoshi Iwamoto, Yasutomo Ota, Yasuhiko Arakawa. 2009-06-23. Photonic crystal nanocavity laser with a single quantum dot gain. https://doi.org/10.1364/oe.17.015975

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