High-frequency ultra-sensitive spin-torque diode based on Co-rich magnetic tunnel junction with in-plane magnetized free layer

Abstract

Spin-torque diodes (STDs) based on magnetic tunnel junctions (MTJs) are newly developing spintronic devices. However, so far, the highly sensitive STDs reported in experiments have a low detection frequency, generally lower than 2 GHz, which limits the application of STDs in HF fields. Here, we develop Co-rich MTJs to enhance in-plane magnetic anisotropy and demonstrate an in-plane magnetized HF ultra-sensitive STD. By selecting the proper field and using an injection locking mechanism, HF microwave detection close to 5 GHz can be realized with a sensitivity greater than 3700 mV mW−1. This result may pave the way to developing spin-torque microwave detectors that are HF and highly sensitive.