Abstract We develop a novel method for fabricating borosilicate millibubble resonators with strong thermo-optical effect. The method is based on self-expanding of air within a two ends sintered borosilicate capillary under the heating of a hydrogen–oxygen flame (HOF). The intrinsic thermo-optical effect of borosilicate millibubble resonator is experimentally demonstrated by a designed novel structure based on the principle of thermometer and the fabricated millibubble resonator has a Q factor exceeding ∼ 104. When filled with ethanol, borosilicate millibubble resonator shows the strong intrinsic thermo-optical effect by exhibiting a linear blue shift of nearly twice of its free spectral range (FSR) under 6.0 mW pump power change, which corresponds to a thermal enhanced tuning sensitivity as high as 0.124 nm/mW. The proposed borosilicate millibubble resonator is anticipated to find applications in optical filtering, all-optical switching, microfluidic sensing as well as all-optical micro-optics devices.

中文翻译：

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自膨胀制造的具有强热光效应的光学微泡谐振器

摘要 我们开发了一种制备具有强热光效应的硼硅酸盐微泡谐振器的新方法。该方法基于在氢氧火焰 (HOF) 加热下两端烧结硼硅酸盐毛细管内的空气自膨胀。通过基于温度计原理设计的新型结构实验证明了硼硅微泡谐振器的本征热光效应，制造的微泡谐振器的 Q 因子超过 104。当填充乙醇时，硼硅微泡谐振器显示出强烈的本征热光效应-光学效应，在 6.0 mW 泵浦功率变化下表现出其自由光谱范围 (FSR) 近两倍的线性蓝移，这对应于高达 0.124 nm/mW 的热增强调谐灵敏度。