Cascaded energy transfer for efficient broad-band pumping of high-quality, micro-lasers.

Low-cost, silicon-compatible on chip high-quality (Q) micro-ring visible lasers are prepd. by coating silica resonators with a combination of org. dyes – AlQ3, DCJTB, and Terrylene. The materials are selected to demonstrate cascaded energy transfer, which concs. the optical pump and overcomes the mismatch in the spectrally and spatially broad pump and the narrow modes of the high-finesse resonant cavity. The broadband pump excites a short wavelength dye in a low Q-factor cavity, there by avoiding the need to resonantly match the pump. Next, the low Q-factor cavity pumps a longer wavelength dye in what is effectively a higher Q-factor cavity, and the process can be repeated, until the desired Q-factor is met. All cavities are on the same resonator and differ only in the wavelength of their operation. Detuning of one cavity with respect to the other cannot occur, eliminating the instability normally assocd. with resonant pumping of high-Q lasers. [on SciFinder(R)]