以單塊二維非週期性晶疇極化反轉鈮酸鋰於Nd:YVO4雷射同時達成電光Q調制及腔內和頻橘黃光產生

Monolithic two dimension aperiodically poled lithium niobate for simultaneous laser Q-switched and intracavity sum frequency generation in a dual wavelength Nd:YVO4 laser

周䓵譽(Pin-yu Chou)

指導教授 ： 陳彥宏

國立中央大學/理學院/光電科學與工程學系/碩士(2014年)

摘要

鈮酸鋰具有良好的壓電、電光、鐵電、熱電以及非線性等特性，為一種具備多種光學特性的晶體，在本論文中利用超晶格結構的方法並透過模擬退火法優化來計算出二維非週期性結構，同時將布拉格光柵與和頻光柵整合於單一結構上。經由黃光微影以及高電場極化反轉的技術將二維非週期性結構製作於Z切鈮酸鋰晶片上，晶片尺寸為長3公分，寬3釐米，厚度500微米。利用此二維非週期性結構所提供的三個倒晶格向量，可以在Nd:YVO4雷射系統中以相同入射角度同時將1064 nm與1342 nm進行布拉格繞射以及和頻轉換，產生出脈衝式橘黃光雷射。

量測結果於Z方向外加電場350伏特時，1064 nm以及1342 nm的繞射效率分別為60 %和55 %。進一步將晶片放置於Nd:YVO4雷射系統中，透過電訊號調制，在攝氏70度時利用單一結構將1064 nm與1342 nm同時進行Q調制以及和頻轉換脈衝式橘黃光雷射輸出，在泵浦5.7瓦特下，可以得到脈寬為8.4 ns、頻寬0.4 nm、脈動雷射間擾動情形8.9 %以及尖端功率512瓦特之脈衝式橘黃光雷射。

關鍵字

鈮酸鋰 ； 和頻轉換 ； Q調制

並列摘要

Compact, high-repetition-rate pulsed visible coherent light sources are attractive for many applications, such as biomedicine, remote sensing, astronomy, and displays. The Q-switched all-solid-state laser technique can be a promising approach to attain such light sources. Moreover, due to the high nonlinearity and highly engineerable characteristics of the quasi-phase-matching(QPM) material, a device as simultaneous a Q-switch and wavelength converter can be realized in a two-dimensional aperiodically poled lithium niobate (APPLN).

In this thesis, we have designed and fabricated a unique 2D APPLN device integrating the functionalities of the Q-switch for two laser lines(1064nm and 1342 nm) simultaneously and sum frequency generator in a Nd:YVO4 laser system to generate pulsed yellow-orange laser, the such device was designed by aperiodic optical superlattice(AOS) technique and optimized by simulated annealing(SA) method.

In operation, 350 volts at repetition rate of 1 KHz drove the device, while the diffraction efficiencies of 1064 nm and 1342 nm of 60 % and 55 % were measured, respectively. At diode pump power of 5.7 watts, a yellow-orange pulse with pulse width of 8.4 ns, bandwidth of 0.4 nm, and peak power of 512 can be obtained, meanwhile, the peak-to-peak fluctuation of 8.9% was also found.

並列關鍵字

Lithium niobate ； Sum frequency generation ； Q-switching

參考文獻

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