Dynamic response of tunneling magnetoresistance sensors to nanosecond current step

We investigate the dynamic response of state-of-the-art CoFeB/MgO/CoFeB sensors to nanosecond current step. We use sensors with different field sensitivity (FS) that is induced by voltage controlled magnetic anisotropy (VCMA). In the sensors rise and response times reach down to 15 ns and 11 ns, respectively and are sensitivity independent. The settling time of the sensors changes with field sensitivity and reaches 335 ns for FS = 24 V/T and 137 ns for FS = 10 V/T. The sensor 3 dB bandwidth estimated from the rise time reaches 15 MHz. This superior dynamic performance of the TMR sensors opens possibilities of using them for high-speed magnetic field and current sensing and controlling their dynamic response by the sensitivity. (C) 2015 Elsevier B.V. All rights reserved.