In this paper, we investigate the quantum fluctuations of subharmonic reflected field from a triple-resonant degenerate optical parametric amplifier (OPA) inside coupled optical resonators, which is driven by the squeezed beam at signal frequency. By controlling the relative phase between the pump beam and the injected signal beam, we can see the quantum fluctuation in the phase direction and amplitude direction due to the parametric down-conversion process in the cavity. Thus, the phase sensitive operation of the compression field is realized due to the quantum interference between the harmonic field of the down converter of OPA and the inner field of the coupled optical resonator. We verified the quantum coherent phenomena of OPA in coupled optical resonators and phase-sensitive manipulations of quantum entanglement for quantum information processing. We realized the electromagnetically induced transparency-like (EIT-like) effect and the optical parameter conversion process at the same time in one optical device. These properties can favor higher manipulation precision and control efficiency, which is more suitable for the integration of quantum-on-chip systems, laying a foundation for the practical application of quantum information.

针对微电子机械系统（MEMS）陀螺温度变化影响其零偏误差的问题, 提出了一种基于粒子群优化（PSO）和径向基函数（RBF）神经网络的陀螺零偏补偿方法。通过RBF神经网络对预处理后的陀螺零偏的温度误差建立模型, 用PSO搜索RBF神经网络的最优参数来提高其泛化能力后, 将PSO-RBF神经网络最优参数用于补偿陀螺零偏。实验结果证明了该算法的有效性, 经PSO-RBF神经网络算法补偿后, MEMS陀螺零偏的最大误差从0.046(°)/s减小到0.0034(°)/s, 标准差从0.0427(°)/s减小到 0.0013(°)/s, 有效提升了陀螺的零偏稳定性。

A novel fluid sensing system based on side-polished optical fiber (SPOF) is proposed, which realizes the fluid replaceability and effective refractive index (RI) sensing characteristics. Numerical investigations demonstrate that the photonic bandgap effect can be obtained if the RI of liquid is higher than that of substrate material in the wavelength range studied. The relationship between bandgap edge wavelength and RI is studied theoretically. The SPOF with a depth of 57 μm is used in the experiment to realize the construction of the fluid channel. After filling three different liquids, the result shows that the wavelength of the bandgap edge has a red shift with RI increased, which is nearly linear in the RI range of 1.56—1.6 with a sensitivity about 5 543.64 nm/RIU. The proposed sensing system can be flexibly applied to the field of fluid characteristic sensing such as biochemical solution characteristic detections.

A novel whispering gallery mode (WGM) strain sensor based on microtube has been proposed, where perceiving strain variations are reported via the dynamical regulation of a whispering gallery mode. The WGMs in the microtube resonator were evanescently excited by a micro-nano fiber fabricated by the fusion taper technique. The structural changes of microtubes under axial strain were simulated with finite element software, and the effect of microtube wall thickness on strain sensitivity was systematically studied through experiments. The experimental results show that the strain sensitivity of thin-walled microtube is found to be 1.18 pm/με and the Q-factor in the order of 4.4×10⁴. Due to its simple fabrication and easy manipulation as well as good sensing performance, the microtube strain sensor has potential applications in high-sensitivity optical sensing.

微机电系统(MEMS)陀螺仪具有体积小、精度高、应用前景广等优点。由于惯性器件材料的热阻值、热应力差异, 对应传感器输出会产生温度滞后效应, 严重影响了陀螺仪零偏稳定性。针对传统陀螺仪温度误差补偿法适应性较差的问题, 该文利用滑动平均算法(MAA), 提出了一种温度滞后零偏补偿模型, 在全温范围内对MEMS陀螺仪零偏进行补偿。实验结果表明, 补偿后陀螺仪工作温度在-30~+90 ℃变化时, 对应的零偏标准偏差从0.21 (°)/s降至0.02 (°)/s, 零偏稳定性提升了近1个数量级。

Theoretical design of a neotype fluidic controlling sensor system based on side-polished optical fiber is proposed. Numerical investigations demonstrate that the higher birefringence and resonance coupling can be achieved by flexible design of the polishing shape and depth in the research wavelength. The fluidic system is beneficial to selective integration of functional materials. The material is integrated into the fluidic system, which can achieve a birefringence up to 6.98×10^-5, and the application of Sagnac thermometer in temperature sensing is studied, and a group of dips with different temperature sensitivities would be observed in the transmission spectra, which is about 1.6 nm/°C by calculating. furthermore, by introducing resonant coupling, single mode single polarization at 1 310 nm is realized. The refractive index (RI) response of the sensing system for a low RI range of 1.39—1.37 is approximately linear, and exhibits a sensitivity of 6 338 nm/RIU. The results show that the proposed neotype fluidic controlling system can be used as a flexible polarization filter or as a potential two-parameter sensor.

A temperature-insensitive polarization filter and a neotype sensor based on a hybrid-circular-hole microstructured op-tical fiber (MOF) are proposed. Numerical investigations demonstrate that the x polarized component of silica core mode can couple to the cladding mode in the researched wavelength, while the y polarized component would not. Fur-thermore, the resonant region can be controlled by changing the diameters or coordinates of the air holes, and the MOF has good performance on stability of temperature. Moreover, the hybrid-circular-hole structure is propitious to selec-tively integrate different functional materials. Two different materials are integrated into this proposed MOF, the ap-plication of the Sagnac interferometer in temperature sensing is studied, and two groups of dips would be observed in the transmission spectra, which have different temperature sensitivities. Therefore, the proposed MOF can be used as a flexible temperature-insensitive polarization filter or potentially applied to a two-parameter sensor.

We experimentally investigate the optical cavity for various coupled regimes with an injected squeezed vacuum state. We measure the quantum fluctuation spectra of the reflected field of an optical cavity using the homodyne detection and present the spectral dependence on the absorption and dispersion properties of the cavity in the under-coupled, critically-coupled, and over-coupled regimes. The spectra lineshape is phase sensitive with the phase shift induced by the cavity. Moreover, we find that the over-coupled optical cavity has obvious advantage in the manipulation of quantum fluctuation.

压缩态光场是一类重要的非经典光场，是产生量子纠缠和进行量子通信的基础，在量子光学研究中具有十分重要的应用价值。本实验通过使用稳定的光学元件和合理的光路系统，简化系统复杂性，使压缩光装置整体结构紧凑、调节方便、稳定度高和可靠性好，通过上述方法，我们利用周期性极化磷酸钛氧钾(PPKTP)晶体获得了稳定的2 dB压缩和8 dB反向压缩的真空压缩光场。本装置的目的在于提供一种稳定的真空压缩光场产生装置。