Materials World Network: Semiconductor Photonic Materials Inside Microstructured Optical Fibers

该项目基于与英国南安普顿大学的合作，旨在提高化合物半导体和非晶氢化族IV半导体光纤的材料质量，使其在包括非线性光学处理、亚波长成像和光纤激光器在内的广泛应用中变得有用。目前半导体光纤的损耗超过1 dB/cm，这在许多半导体光子器件中通常被认为是实际应用的阈值损耗。晶界散射是复合半导体光纤的主要损耗机制，通过改进光纤内材料沉积技术，这种损耗机制将得到降低。氢化硅和锗纤维的损耗也将通过消除导致光纤芯中光散射的空隙和改进材料沉积技术来减少，以允许更好地钝化导致损耗的缺陷。这些改进的低损耗化合物半导体和非晶氢化族半导体光纤的二阶和三阶非线性光学特性将从非线性光学器件的角度进行表征。由这些材料组成的芯包层纤维结构也将用于亚波长、高分辨率红外成像。不同成分的新型化合物半导体光纤也将被沉积，以扩展可在光纤几何中开发的材料性能范围。该项目汇集了宾夕法尼亚州立大学团队在材料合成、结构和光学表征方面的互补专业知识，以及南安普顿大学团队在导波器件方面的专业知识。学生们将在大西洋的两个方向进行几周到一个月的访问，以保持两组之间强有力的合作关系。这些访问将通过网络讨论和演示以及基于计算机的视频会议补充正在进行的协作互动。美国学生将在南安普顿光电研究中心接触世界一流的光纤制造和表征设施。英国学生将在宾夕法尼亚州立大学学习材料合成和表征。这种天然的伙伴关系有望通过提出的材料研究将晶体半导体和非晶氢化半导体纤维领域推向实际应用。拓展工作包括访问当地学校，接待宾夕法尼亚州立大学实验室的本科生，以及PI和学生参加宾夕法尼亚州立大学为2-12年级学生举办的动手科学营。这些营地有大量未被充分代表的群体参与，并为所有参与者提供高质量、高吸引力的科学指导。

This project, based on collaboration with the University of Southampton in the United Kingdom, seeks to improve the materials quality of compound semiconductor and amorphous hydrogenated group IV semiconductor optical fibers such that they become useful for a wide range of applications, including non-linear optical processing, subwavelength imaging, and fiber lasers. Current semiconductor optical fibers have losses in excess of 1 dB/cm, which is often considered to be the threshold loss for practical application in many semiconductor photonic devices. The grain boundary scattering that is the primary loss mechanism in compound semiconductor fibers will be reduced by improving in-fiber materials deposition techniques that the US/UK groups have pioneered. The loss in hydrogenated silicon and germanium fibers will also be reduced by eliminating voids that lead to light scattering in fiber cores and improving materials deposition techniques to allow for better passivation of defects that give rise to loss. The second and third order non-linear optical properties of these improved low loss compound semiconductor and amorphous hydrogenated group IV semiconductor fibers will be characterized with a view toward non-linear optical devices. Core cladding fiber structures composed of these materials will also be fabricated for sub-wavelength, high resolution infrared imaging. New compound semiconductor fibers with different compositions will also be deposited to extend the range of materials properties that can be exploited in the fiber geometry.This project brings together the complementary expertise in materials synthesis and structural and optical characterization of the Penn State team and with the expertise in guided wave devices of the Southampton team. Students will travel in both directions across the Atlantic for visits of a few weeks to a month to maintain the strong collaborative ties between the two groups. These visits will supplement ongoing collaborative interactions via web-based discussions and presentations as well as computer-based video conferencing. US students will be exposed to the world class fiber fabrication and characterization facilities at the Southampton Optoelectronics Research Centre. UK students will learn about materials synthesis and characterization at Penn State. This natural partnership is anticipated to move the field of crystalline semiconductor and amorphous hydrogenated semiconductor fibers towards practical application through the proposed materials research. Outreach efforts include visits to local schools, hosting undergraduate students in the Penn State Laboratories, and participation by the PI's and students in hands-on science camps hosted at Penn State for students from grades 2-12. These camps have substantial participation by underrepresented groups and provide high quality, highly engaging science instruction for all attendees.