High-efficiency frequency conversion by phased cascading of nonlinear optical elements

Summary form only given. We present a technique whereby the frequency-doubled output power of a laser system is increased by a factor of two without increasing the size of the pump laser. The technique uses multiple doubling crystals in a tandem arrangement with inter-crystal phase plates to maintain proper phasing of the fields. The result leads to a savings of cost, power, and weight in operational systems. The process is demonstrated with a commercial 19 Watt cw mode-locked Nd:YAG laser and two temperature-tuned lithium triborate (LBO) crystals.<
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