Single-mode delivery of 250 nm light using a large mode area photonic crystal fiber.
Single-mode delivery of 250 nm light using a large mode area photonic crystal fiber.
复制标题
使用大模式面积光子晶体光纤单模传输 250 nm 光。
作者：
Naoji Yamamoto;Leigang Tao;A. Yalin
我们证明了大模场面积（LMA）光子晶体光纤（PCF）可以用作单模250 nm激光的跳线。研究了四倍频二极管激光器输出的250 nm光束通过10 μ m三角形结构的LMA PCF的传输特性。我们已经实现了单模输出，耦合损耗为1.8 +/- 0.6 dB，传输损耗为1.5 +/- 0.2 dB/m。临界弯曲损失半径约为6 cm。的传输损耗进行了比较与出版的散装二氧化硅测量。长时间手术后观察到光致损伤的影响，并研究了激光功率和时间的函数。光学损伤主要发生在光纤输入端，并且可以通过劈开光纤输入端来部分地改善。对于< approximately 0.3 mW stable operation can be achieved for periods of >许多基于实验室的应用来说，40小时的输入功率水平是足够的。结果表明，在阶跃折射率单模光纤不容易获得的光谱区域中，这些光纤用于单模光束传输的实用性。
We demonstrate that large mode area (LMA) photonic crystal fibers (PCFs) can be used as single-mode patch-cords for 250 nm laser light. We have studied the transmission of the 250 nm output beam of a frequency-quadrupled diode laser through a triangular structure LMA PCF with 10 microm core. We have achieved single-mode output with coupling loss of 1.8 +/- 0.6 dB and transmission loss of 1.5 +/- 0.2 dB/m. The critical bend loss radius is approximately 6 cm. The transmission loss is compared with published bulk silica measurements. Effects of optically induced damage were observed after prolonged operation and have been studied as function of laser power and time. The optical damage occurs primarily at the fiber input and can be partly ameliorated by cleaving the fiber input. For input power levels of < approximately 0.3 mW stable operation can be achieved for periods of >40 hours which is sufficient for many laboratory based applications. The results show the utility of these fibers for single-mode beam delivery in a spectral region where step-index single-mode fibers are not readily available.