Bérubé J P, Messaddeq S H, Bernier M, Skripachev I, Messaddeq Y, Vallée R
Opt Express. 2014 Oct 20;22(21):26103-16. doi: 10.1364/OE.22.026103.
The photosensitivity of GeS(x) binary glasses in response to irradiation to femtosecond pulses at 800 nm is investigated. Samples with three different molecular compositions were irradiated under different exposure conditions. The material response to laser exposure was characterized by both refractometry and micro-Raman spectroscopy. It is shown that the relative content of sulfur in the glass matrix influences the photo-induced refractive index modification. At low sulfur content, both positive and negative index changes can be obtained while at high sulfur content, only a positive index change can be reached. These changes were correlated with variations in the Raman response of exposed glass which were interpreted in terms of structural modifications of the glass network. Under optimized exposure conditions, waveguides with positive index changes of up to 7.8 x 10(-3)and a controllable diameter from 14 to 25 μm can be obtained. Direct inscription of low insertion losses (IL = 3.1 - 3.9 dB) waveguides is demonstrated in a sample characterized by a S/Ge ratio of 4. The current results open a pathway towards the use of Ge-S binary glasses for the fabrication of integrated mid-infrared photonic components.
研究了GeS(x)二元玻璃对800 nm飞秒脉冲辐照的光敏性。对具有三种不同分子组成的样品在不同曝光条件下进行辐照。通过折射测量和显微拉曼光谱对材料对激光曝光的响应进行了表征。结果表明，玻璃基质中硫的相对含量会影响光致折射率变化。在低硫含量下，可获得正、负折射率变化，而在高硫含量下，只能实现正折射率变化。这些变化与曝光玻璃的拉曼响应变化相关，这些变化根据玻璃网络的结构改性进行了解释。在优化的曝光条件下，可获得正折射率变化高达7.8×10(-3)且直径可控在14至25μm的波导。在以S/Ge比为4为特征的样品中展示了低插入损耗（IL = 3.1 - 3.9 dB）波导的直接写入。当前结果为使用Ge-S二元玻璃制造集成中红外光子组件开辟了一条途径。
