SBIR Phase I: Improved Metal Oxide Magneto-Optical Indicator Films and Method of Fabrication

该小型企业创新研究第一阶段项目旨在研究增强型磁光石榴石薄膜的可行性，该薄膜能够通过法拉第偏振旋转将磁场强度转换为光学数据，并使用一种制造全介质金属氧化物的新方法来制备此类薄膜。这种类型的薄膜被称为“面内”薄膜，因为磁化矢量位于衬底的平面内，并且必须区别于大量用于光通信(例如，隔离器和环行器)以及某些电流传感器的“平面外”厚膜。根据投影薄膜的特性和所提出的系统设计，估计磁光成像器(MOIS)可以分辨小于200 nm的空间磁场特征和小于100纳秒的磁场强度(相当于小于10微安的电流)。MOI薄膜还能够扩展到GHz范围内的频率响应，从而使光学信号处理应用成为可能。该项目更广泛的影响/商业潜力源于成像系统中的潜在应用，这些成像系统可以对损坏的磁数据存储设备、半导体晶片中的电流成像工具以及电力行业的磁电流传感器等进行成像。此前，MOI薄膜的几种应用已经商业化，但由于供应不确定，商业努力一直受到阻碍。社会和教育利益将包括一个额外的电磁学课堂教学工具，一个进行高温超导体研究的新方法，以及使国家电网和电力基础设施更安全、更可靠的设备的潜力。

This Small Business Innovation Research Phase I project is intended to investigate the feasibility of enhanced magneto-optic thin garnet films, capable of converting magnetic field intensity to optical data using Faraday polarization rotation, and fabrication of such films using a novel method of manufacturing all-dielectric metal oxides. This type of thin film is known as an "in-plane" film because the magnetization vector lies in the plane of the substrate and must be distinguished from the "out-of-plane" thick films that are used in large quantities in optical communications (e.g. for isolators and circulators), and in some electrical current sensors. With the projected film properties and proposed system design, it is estimated that magneto-optical imagers (MOIs) can resolve spatial magnetic features of less than 200 nm and magnetic field strengths of less than 100 nanotesla (which corresponds to electrical currents of less than 10 µA). The MOI films are also capable of frequency responses extending into the GHz range, making optical signal processing applications possible. The broader impact/commercial potential of this project originates from potential applications in imaging systems which can image damaged magnetic data storage devices, tools for imaging electrical currents in semiconductor wafers, and magnetic current sensors for the electrical power industry, among others. Several applications of MOI films have been commercialized previously, but commercial efforts have been hampered by an uncertain supply of the films. Societal and educational benefits will include an additional tool for classroom instruction in electromagnetics, a new method for conducting research into high temperature superconductors, and the potential for devices which will make the nation's electrical grid and power infrastructure safer and more reliable.