利用半導體雷射激發Cr4+:Forsterite所放射的頻譜範圍1.1~1.4μm不僅對於生物的軟性組織有極小的吸收，對於光通訊也可避開1.4μm附近水分子吸收。因此，Cr4+:Forsterite晶體作為寬頻光源有極佳的發展潛力。

本論文利用雷射基座生長法(LHPG)生長出纖核直徑70μm的Cr4+:Forsterite單纖衣晶體光纖，藉由理論分析與特性量測來探討各種因素對於ASE寬頻光源斜線效率的影響，包括晶纖的傳輸損耗與吸收係數、晶纖長度對於ASE功率的增進、激發光源極化與波長的影響、環境溫度的改變對ASE斜線效率的影響。目前晶體光纖纖核直徑固定為70μm。

用半導體雷射907nm、2.16W激發下，長度10.6cm的Cr4+:Forsterite單纖衣晶體光纖可產生1mW、中心波長1116nm、3dB頻寬200nm的ASE寬頻光源。，用雷射二極體1550nm激發下，所量測出來的晶體光纖傳輸損耗範圍是0.006~0.02cm-1。用極化激發光源1064nm激發下，晶纖內a、b晶軸的ASE斜線效率差距為40~80%。改變環境溫度可了解ASE斜線效率對於環境溫度的衰退幅度為0.78%/℃。

The emission spectrum of Cr4+:Forsterite covers 1.1 to 1.4μm, with minimal absorption for biological soft tissue and for standard optical fibers having OH- absorption near 1.4μm. Therefore, Cr4 +: Forsterite crystal based broadband light sources have excellent potential.

In this research, the factors that determine the slope efficiency of amplified spontaneous emission(ASE) broadband light source were explored through theory and experiments. They included the propagation loss and absorption coefficient of crystal fiber, the length of crystal fiber, the polarization and wavelength of the pump laser, and ambient temperature. The core size of fiber was limited to 70μm in the meantime.

ASE power of 1mW was obtained from a 10.6cm-long Cr4 +: Forsterite single-clad crystal fiber when pumped with a non-polarized 907nm laser diode of 2.16W. Broadband emission spectrum exhibited a 3dB bandwidth of 200nm and a peak wavelength of 1116nm. The propagation loss of crystal fibers was in a range of 0.006~0.02cm-1 measured with a 1550nm laser diode. The ASE slope efficiency difference between a-axis and b-axis of Cr4 +: Forsterite crystal fiber was 40%~80% measured with a polarized 1064nm laser diode. The temperature sensitivity of the ASE slope efficiency was -0.78%/℃.

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