Microwave reflection imaging using a magnetic tunnel junction based spintronic microwave sensor

摘要

A far-field microwave imaging technique has been developed using a spintronic sensor based on a magnetic tunnel junction (MTJ). Such a sensor can directly rectify a microwave field into a dc voltage signal using the Seebeck effect. Thanks to the high conversion efficiency of the microwave rectification in MTJs, the microwave power sensitivity of the spintronic sensor is on the order of 1-10mV/mW. This high sensitivity allows the sensor to directly measure the coherent spatial scattered microwave field distribution, which gives it the ability to non-destructively detect hidden objects down to a few wavelengths in size.