高灵敏度光学非线性测量技术的研究

Identifying material's nonlinear optical response for today's photonic applications is an ongoing effort.Therefore the optical nonlinearity measurement technique is the key for characterizing materials and device's nonlinear optical response. The destination of this program is to put forward and develop a novel optical nonlinearity measurement technique. The sensitivity of this method is two orders of magnitude larger than traditional measurement technique. The major element of the program is organized as follows: Sec.Ⅰdescribes the high sensitive single-shot third-order nonlinear refraction measurement system based on the phase object Z-scan configuration. Our goal is to study the mechanism of sensitivity enhancement of this technique and to achieve maximum sensitivity by optimizing the transmission and phase delay of phase object in the measurement system. Sec. Ⅱpresents a new time-resolved pump-probe system, which measures the dynamics response of third-order nonlinear refraction. Compared to other time-resolved nonlinear refraction spectroscopy technique such as time-resolved Z-scan measurement and time-resolved nonlinear imaging technique with phase object, this modified pump-probe technique is simpler and much more sensitive. Sec. Ⅲ presents variant versions of modified measurement system. The transmissive single-shot measurement technique is able to determine the nonlinear absorption coefficient and nonlinear refraction index simultaneously. The reflective single-shot measurement technique could be used to characterize the surface optical nonlinearity of nontransparent ultrathin film. This high sensitive optical nonlinearity measurement technique is of potential importance to the research of nonlinear optical material, especially low damage-threshold thin film.

光学非线性测量技术是研究材料光学非线性的必要工具。本项目研究一种高灵敏度材料光学非线性测量技术,与传统的光学非线性测量技术相比，其灵敏度可提高两个数量级。主要研究内容包括：在相位物体Z-scan技术基础上发展高灵敏度光学非线性测量系统；探索系统灵敏度提高的原理，研究系统中相位物体的透过率、相位延迟、及半径大小等因素对系统灵敏度的影响，优化系统,进一步提高系统测量灵敏度。系统中引入泵浦光激发，开展高灵敏度瞬态光学非线性折射测量技术研究。研究反射相位物体单脉冲测量技术，以测量材料表面、非透明衬底薄膜的光学非线性。该研究将对光学非线性测量技术的发展以及非线性光学材料，特别是易损伤材料，如薄膜的光学非线性研究具有极其重要的意义。

随着光通信和光信息处理等领域技术的飞速发展，非线性光学材料的研究日益重要。便捷可靠的测量方法是寻找理想非线性材料的必要工具。本项目研究了一种高灵敏度材料光学非线性测量技术,与传统的光学非线性测量技术相比，其灵敏度得到了较大的提高。项目主要完成的内容包括：在相位物体Z-scan技术基础上发展了高灵敏度光学非线性测量系统；探索系统灵敏度提高的原理，研究了系统中相位物体的透过率、及半径大小等因素对系统灵敏度的影响，优化系统，进一步提高系统测量灵敏度。在高灵敏度单脉冲光学非线性测量系统中引入泵浦光激发，开展高灵敏度瞬态光学非线性折射测量技术研究。提出了移动透镜反射Z扫描测量技术，以测量材料表面、非透明衬底薄膜的光学非线性。利用改进的光学非线性测量技术研究了不同材料的光学非线性特性。本项目所完成的光学非线性测量技术将对光学非线性测量技术的发展以及非线性光学材料，特别是易损伤材料，如薄膜的光学非线性研究具有极其重要的意义。