Long wavelength quantum-dot lasers selectively populated using tunnel injection

Using measured amplified spontaneous emission data, we have derived and analysed the carrier distribution of a five-layer tunnelling injection quantum-dot structure at temperatures of 300 K and 350 K. The results are consistent with the direct injection of electrons from the injector well into a subset of lower energy dot states. The carrier distribution spectra contain features which suggest that dots of a particular size within the ensemble are preferentially populated leading to a reduced spectral broadening of the emission.