Photonic crystal nanocavity laser with a single quantum dot gain.
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 10(8) 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 using the single quantum dot gain.
Nomura
Masahiro
M
Institute for Nano Quantum Information Electronics, Institute of Industrial Science, The University of Tokyo, Tokyo 153-8505, Japan. nomura@iis.u-tokyo.ac.jp
Kumagai
Naoto
N
Iwamoto
Satoshi
S
Ota
Yasutomo
Y
Arakawa
Yasuhiko
Y