Fig. 3 (IMAGE) Osaka University Caption Schematic of the microwave amplification (left) and magnetic field dependence of the microwave power reflectivity spectra (right). The reflected microwave is amplified by the dc voltage (V<sub>dc</sub>) biased MTJ. In our experiment, we have obtained a microwave power reflectivity of more than 1.6 under an external magnetic field of 50 mT and frequency of 0.4 GHz. Credit Osaka University, National Institute of Advanced Industrial Science and Technology, and Grenoble Alpes University Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.