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A novel design for a highly efficient 1-kHz single-frequency green laser is proposed.An efficient singlefrequency laser pulse output at 532-nm wavelength may be obtained by combining the injection seeding with intracavity frequency doubling in a compact U-shaped cavity formed by two plano dichroic mirrors in an end-pumping arrangement.The laser is capable of producing green pulses with a total energy of 6.3 mJ at a pulse repetition rate of 1 kHz.The pulse width is about 10 ns and the optical-optical efficiency from the 808-nm pump source to the 532-nm green output is around 12.7%. 相似文献
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In this paper, the deposition of Cu13 onto Cu(1 1 1) surface through argon buffer layers was investigated by molecular dynamics (MD) simulations. The interactions between Cu-Cu, Cu-Ar, and Ar-Ar were described by Finnis-Sinclair (FS) tight-binding potential and L-J potential, respectively. The impact energy was chosen to be 2-6 eV/atom in order to compare with experimental results. It was observed that with Ar-buffer layers, the Cu cluster deposited on the surface may retain its free cluster symmetry (Ih). Whereas, on originally bare Cu surface, the deposited Cu cluster lost its original symmetry completely and was recrystalized to have the same fcc structure as the substrate. The Ar-buffer dissipates most of the translational energy of the incident cluster. Therefore, it prevents the cluster from being overheated upon impinging. Furthermore, the interaction between Ar and Cu benefits the confinement of the cluster structure. Our study shows that with Ar-buffer layers, the lateral spread of deposited clusters is 20% smaller than that on the bare Cu surface. This is consistent with the experimental findings. 相似文献
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Experimental investigation ofd Nd:YAG monolithic nonplanar ring lasers operated at 1123 nm wavelength is presented. Stable single-frequency 1123 nm laser output has been obtained with successful suppression of the strong 1064 nm radiation. Single-frequency output power of 1.25 W is demonstrated with a pump power of 3.98 W at 808 nm, which gives a slope efficiency of 39%. The laser frequency tuning range is over 3 GHz, and the average tuning rate with temperature is -2.6 GHz/ degrees C. A strong iodine absorption line can be covered within the laser frequency tuning range. 相似文献