High-performance of site-controlled and ultra-low density InAs/(In)GaAs quantum dots

To obtain communications band single photon source, one of the effective approaches is to convert site-controlled and low-density quantum dots(QDs) required on the patterned substrates by molecular beam epitaxy(MBE). In order to overcome such difficulty, growth of site-controlled QDs on a pre-patterned substrates were proposed, the In(Ga)As/GaAs QDs grown on the high reflectivity distributed Bragg reflector mirror composed of a limited thickness of the wavelength of the micro-cavity center. The spectrum measured at 10K, the wavelength was 1251μm. The results showed that the site-controlled and low-density QDs growth technology prepared not only had high optical quality, but also for real single photon emission.