SBIR Phase I: Flux-Gated Spin-Dependent-Tunneling Sensors

这项小型企业创新研究（SBIR）第一阶段项目基于创新的磁通调制方法开发新型自旋依赖隧道（SDT）磁场传感器设备。该程序确定了两种模式的“磁通门控”作为截断或扫磁场的手段，这是由SDT传感器感测。磁通门方法被提出作为增强已经有前途的SDT磁传感器的功能。第一种方法提供了一种低功耗解决方案，用于提高SDT信噪比，特别是在存在1/f噪声的低频时。第二种方法可以确定绝对场强。这些新想法的成功发展将导致小型、固态、廉价、低功耗、高分辨率磁场传感器的发展。这些传感器可用于离散或紧凑阵列的各种应用，包括金属结构缺陷的无损评估。该研究的商业应用包括金属结构缺陷的无损评估；磁性或金属物体的探测、监视和跟踪；安全系统;磁介质感应——包括货币评估和识别，以及磁卡读卡器。

This Small Business Innovation Research (SBIR) Phase I project develops novel spin-dependent-tunneling (SDT) magnetic-field sensor devices based on innovative methods of flux modulation. The program identifies two modes of "flux gating" as a means of chopping or sweeping the magnetic field which is sensed by the SDT transducers. The flux gating methods are proposed as enhancements to the functionality of the already promising SDT magnetic sensor. The first method offers a low-power solution for increasing the SDT signal-to-noise ratio especially at low frequencies where 1/f noise is present. The second method enables the determination of absolute field magnitudes. Successful development of these novel ideas will lead to the advancement of small, solid-state, inexpensive, low-power, high resolution magnetic-field sensors. These sensors can be used discretely or in compact arrays for diverse applications including non-destructive evaluation of metallic structure flaws.The commercial applications of the research include non-destructive evaluation of flaws in metallic structures; detection, surveillance and tracking of magnetic or metallic objects; security systems; and magnetic media sensing-which includes currency evaluation and discrimination, and magnetic card readers.