Hu Jinliang, Liu Sheng, Wu Xiang, Liu Liying, Xu Lei
Key Lab for Micro and Nanophotonic Structures (Ministry of Education), Department of Optical Science and Engineering, School of Information Science and Engineering, Fudan University, Shanghai 200433, China.
Department of Physics, Fudan University, Shanghai 200433, China.
Sensors (Basel). 2019 Jul 22;19(14):3223. doi: 10.3390/s19143223.
We report on a novel optical microcavity sensing scheme by using the orthogonal demodulation Pound-Drever-Hall (PDH) technique. We found that larger sensitivity in a broad range of cavity quality factor (Q) could be obtained. Taking microbubble resonator (MBR) pressure sensing as an example, a lower detection limit than the conventional wavelength shift detection method was achieved. When the MBR cavity Q is about 10-10, the technique can decrease the detection limit by one or two orders of magnitude. The pressure-frequency sensitivity is 11.6 GHz/bar at wavelength of 850 nm, and its detection limit can approach 0.0515 mbar. This technique can also be applied to other kinds of microcavity sensors to improve sensing performance.
我们报道了一种采用正交解调庞德-德瑞弗-霍尔（PDH）技术的新型光学微腔传感方案。我们发现，在很宽的腔品质因数（Q）范围内都能获得更高的灵敏度。以微泡谐振器（MBR）压力传感为例，实现了比传统波长偏移检测方法更低的检测限。当MBR腔的Q约为10⁻¹⁰时，该技术可将检测限降低一到两个数量级。在850 nm波长下，压力-频率灵敏度为11.6 GHz/bar，其检测限可接近0.0515 mbar。该技术还可应用于其他类型的微腔传感器，以提高传感性能。
