一般單模、可調的連續波固態雷射大多都是採用，在共振腔內加入標準具、稜鏡或者是光柵等光波長選擇元件。然而我們所採用一種新式的光學元件-體積式布拉格光柵 (Volume Bragg grating, VBG) 加上短線型共振腔的結構來達到單模可調的連續波固態雷射。VBG它是利用全像原理，將其記錄於光熱折變 (Photo-thermal refractive, PTR) 玻璃中，由Oleg M. Efimov等人所發展出來的一個新式光學元件。PTR玻璃有許多優點，例如：大的穿透頻寬、高的損害閥值、好的熱穩定性和可控制折射率變化，所以PTR VBG可以當成一個理想窄頻寬雷射鏡子。此外，PTR VBG會隨溫度上升可使它的繞射中心波長增加來調整雷射輸出的波長。我們首先達成Nd:GdVO4雷射在1071 nm附近的雷射輸出，當VBG的溫度從30 ºC改變至184 ºC，波長可從1070.26 nm調至1071.53 nm，共調了1.27 nm。另外我們可以架構一V型共振腔Nd:GdVO4雷射，並且利用VBG當作一面反射及輸出耦合的鏡子，並且改變角度來降低它的繞射波長，入射至VBG玻璃的表面與法線夾角從14º改變至21º，波長可從1062 nm調至 1066.3 nm，共調了4.3 nm。

In general, cw solid state laser of single mode and tuning wavelength laser usually used etalon, prisms or grating. However, we used new optical element - Volume Bragg grating (VBG) to integrate short linear cavity to achieve single mode tuning cw solid state laser. VBG was make holography use of ultraviolet (UV) and record to Photo-thermal refractive (PTR) glass. It is the new optical element component coming out invented by Oleg M. Efimov et. The PTR VBG had many advantages such as large transparent range, high damage threshold, good thermal stability, and has controllable refraction index change. Therefore, a PTR VBG can work for an ideal narrow band laser mirror. Tuning the temperature or changing incident angle of the Bragg grating can shift the central lasing peak to tuning laser emission central wavelength. The 1070 nm lasing action of Nd:GdVO4 is demonstrated for the first time to our knowledge. The PTR VBG temperature range from 30 °C to 156 °C, and lasing wavelength can from 1070.26 nm to 1071.53 nm. Total tuning range is 1.27 nm. In addition, we have constructed a V-cavity Nd:GdVO4 laser using the VBG as the folding mirror and output coupler. And changing deflected angle from 14º to 21º and tunable wavelength from 1062 nm to 1066.3 nm, total tuning ranging is 4.3 nm.

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