Highly sensitive spin-torque diodes based on in-plane magnetized magnetic tunnel junctions

We investigate the highly sensitive spin torque diode (STD) effect in a magnetic tunnel junction (MTJ) with an in-plane polarizer and an in-plane free layer. Under injection locking mechanisms, a high rectification voltage of 12mV is obtained with an input radio frequency power of 1 mu W under direct current bias current and a weak magnetic field, corresponding to a high sensitivity of 12 000 mV/mW. In addition, we use the nonlinear rectification characteristics of STD to mimic a neuron with a ReLU-like activation function to perform the recognition of handwritten digits in the Mixed National Institute of Standards and Technology database, where a produced accuracy of up to 93.53% is obtained. These findings suggest that the MTJ with in-plane magnetized electrodes holds promising potential in developing high sensitivity STDs for Internet of Things applications and neuromorphic computing. Published under an exclusive license by AIP Publishing.