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Vertical external cavity surface emitting lasers with emitting wavelength of 1040-1200 nm grown by metal organic chemical vapor deposition

The combination of solid-state laser technology and semiconductor laser technology bloomed the technology of vertical external cavity lasers (VECSELs). This technology has developed rapidly and is attracting more and more scientists’ attention in the last few years. Recently, VECSELs in the wavelength range of 1040nm-1200nm which can achieve green to yellow light emission by double frequency generation are realized in our group. A series of VECSEL gain chip structures are deposited using MOCVD. Based on the analyze of band gap and resonant periodic gain (RPG) structure, the quantum wells of the gain chip are placed at the loops of the resonant stand wave to obtain maximum optical gain. After the removal of substrate, the gain chips are tested in the flat concave short cavity with 2% output mirror. The maximum output power of 1064nm laser is 1.6W at a pump power of 10W and the best optical to optical conversion efficiency is 32%. Using the gain chip, we also obtain the double frequency laser emitting at 530nm-580nm, including 532nm, 566nm, 569nm, and 572nm et al., which is in the range of yellow green of visible spectrum. The 532nm green laser can reach a 24mW continuous output power and the other yellow green laser can reach at least 5mW continuous output power. By the optimization of the gain chip and laser cavity design, this technology can be used in the field of laser projection, nonlinear microimaging, laser therapy and atomic or molecular physics.