Optical gain and green/red vertical cavity surface emitting lasing from cdse-based colloidal nanocrystal quantum dot thin films

We demonstrate robust excitonic gain from colloidal close-packed, CdSe-based nanocrystal quantum dot thin films at record low threshold excitation energy of 90 μJ/cm
²
for amplified spontaneous emission. The optical gain is employed in pulsed optically pumped quantum dot vertical cavity surface emitting lasers in the green and the red, respectively.