Subwavelength Structures Based on Metamaterials and Spintronic Devices for Microwave Detection and Imaging
University of Delaware/NASA Glenn Research Center, Space Technology Mission Directorate
This NASA EPSCoR program aims to develop novel microwave devices based on metamaterial concepts and spintronic devices. Metamaterials refer to a class of materials that do not occur naturally and are characterized with unique electromagnetic (EM) properties. The field of spintronics explores the magnetic properties (spin) of electronics, in addition to and sometimes in place of electronic properties (charge) of electronics. Two major advances have been achieved in this research. First, a microwave imaging device has been developed which is characterized with subwavelength pixel size and near perfect efficiency. Besides the microwave imaging applications, the concept can also be extended to construct a universal energy adaptor that converts EM wave energy into other forms of energy with negligible losses. Second, a new mechanism to significantly enhance and tune ferromagnetic
resonance frequency (FMR) has been proposed and demonstrated. The enhancement and tunability of FMR is much larger than any existing methods. FMR phenomenon has been widely used in many microwave devices and is an important parameter used in computer harddisks and magnetic memory. A spintronic microwave device with tunable frequency has been demonstrated. The device is capable of detecting microwave frequency, intensity, and phase. Consequently, such a device can be used to construct an on-ship network analyzer and spectrum analyzer. These significant advances have been achieved with an interdisciplinary team of physicists, material scientists, and engineers and the close interaction between the university and a NASA research center. The program has also trained undergraduate and graduate students as future generations of scientists in critical areas. Prof. John Q. Xiao (Science PI, University of Delaware), and a graduate student working on microwave experiments.
Experiment setup of the spin valvebased (SV) microwave detector. (b) The SV response at different temperatures. The resonant frequencies of the exchange mode decreases with increasing temperature. The inset shows the gradual increase of the resonance magnitude and decrease of frequency with increasing temperature. (c) The resonant frequency for coherent and exchange modes and extracted interlayer coupling strength as a function of the temperature. The inset shows that the voltage sensitivity is inversely proportional to the frequency.
Dr. Rainee N. Simons, PhD, NASA Technical Monitor, Glenn Research Center, SMD NASA EPSCoR Stimuli 2014-15
Published on Dec 14, 2015
NASA Office of Education’s Aerospace Research & Career Development (ARCD) is pleased to release NASA EPSCoR Stimuli, a collection of univers...