Soft-Lithographed Up-Converted Distributed Feedback Visible Lasers Based on CdSe-CdZnS-ZnS Quantum Dots

The development of a solution-deposited up-converted distributed feedback laser prototype is presented. It employs a solgel silica/germania soft-lithographed microcavity and CdSeCdZnSZnS quantum dot/solgel zirconia composites as optical gain material. Characterization of the linear and nonlinear optical properties of quantum dots establishes their high absorption cross-sections in the one- and two- photon absorption regimes to be 1 x 10-14 cm2 and 5 x 104 GM, respectively. In addition, ultrafast transient absorption dynamics measurements of the graded seal quantum dots reveal that the Auger recombination lifetime is 220 ps, a value two times higher than that of the corresponding CdSe core. These factors enable the use of such quantum dots as optically pumped gain media, operating in the one- and two-photon absorption regime. The incorporation of CdSeCdZnSZnS quantum dots within a zirconia host matrix affords a quantum-dot ink that can be directly deposited on our soft-lithographed distributed feedback grating to form an all-solution-processed microcavity laser.