US Patent 7778301 - Quantum dot lasing in room temperature liquid solution

http://ip.com/patent/US7778301

CdS nanocrystals have been observed to have excellent lasing characteristics in the blue spectral range. However, this lasing has required low temperature operation (below 170 Kelvin). This patent from Georgia Tech. Research teaches a system implementing CdS quanum dot lasers at room temperature. Claim 1 reads: 

1. Lasing apparatus comprising:

a room temperature liquid solution comprising quantum dots that each have an average diameter between 3 and 6 nanometers, and wherein all quantum dots in the liquid solution are substantially the same size, and wherein each quantum dot is capped with a capping material that passivates and protects the surface and acts to suspend the quantum dot in the liquid solution;

reflective cavity apparatus for confining the room temperature liquid solution; and

apparatus for exciting the room temperature liquid solution to induce lasing of the quantum dots.