We developed a new method to deposit deoxyribonucleic acid (DNA) solid film selectively only on the core of an optical fiber facet with a variable thickness, by optically trapping an aqueous DNA droplet during an optimal drying process. We experimentally demonstrated an ultra-compact DNA Fabry-Perot interferometer (FPI) on the fiber core in a columnar shape with a diameter of ~10 μm and variable height from 2.0 to 4.5 μm. Utilizing the highly confined DNA-FPI and its unique thermo-optical properties with a large negative thermo-optical coefficient of -5.91 × 10⁻⁴/ °C at λ = 1550 nm, we realized a very large temperature sensitivity of -2.42 nm/ °C in the spectral domain and a power change of -0.43 dB/ °C in the biologically important temperature range from 30 to 80 °C. The proposed sensor also showed a fast temporal response with an average rise time of 0.62 s and fall times of 1.16 s. The proposed device structure can be readily applied in situ real-time temperature monitoring applications in microscopic environment as well as in various bio-chemical sensing.

我们开发了一种新方法，通过在最佳干燥过程中光学捕获含水的DNA液滴，将脱氧核糖核酸（DNA）固体膜选择性地仅沉积在厚度可变的光纤小平面的核心上。我们通过实验证明了纤维芯上的超紧凑型DNA Fabry-Perot干涉仪（FPI）呈圆柱状，直径约为10μm，高度从2.0到4.5μm不等。利用高度局限的DNA-FPI及其独特的热光学特性，在λ处具有-5.91×10 ^-4 /°C的大负热光学系数 = 1550 nm，我们在光谱域内实现了-2.42 nm /°C的非常大的温度灵敏度，并且在30至80°C的重要生物学温度范围内实现了-0.43 dB /°C的功率变化。所提出的传感器还显示出快速的时间响应，平均上升时间为0.62 s，下降时间为1.16 s。所提出的设备结构可以很容易地在微观环境以及各种生物化学传感领域中进行原位实时温度监测应用。