2022/11/14 by Rie Matsumoto, Shinji Yuasa, Matsumoto, Rie +3
Engineering · Materials Science · Physics and Astronomy · #Advanced Memory and Neural Computing #FOS: Physical sciences #Magnetic and transport properties of perovskites and related materials #Magnetic properties of thin films #Mesoscale and Nanoscale Physics (cond-mat.mes-hall) #Statistical Mechanics (cond-mat.stat-mech)
paper · pdf · doi:10.48550/arxiv.2211.07148
openalex publication_date 2022/11/14 · openalex created_date 2023/02/11 · openalex updated_date 2026/07/28
Voltage-induced dynamic switching in magnetic tunnel junctions (MTJs) is a writing technique for voltage-controlled magnetoresistive random access memory (VCMRAM), which is expected to be an ultimate non-volatile memory with ultra-low power consumption. In conventional dynamic switching, the width of sub-nanosecond write voltage pulses must be precisely controlled to achieve a sufficiently low write-error rate (WER). This very narrow tolerance of pulse width is the biggest technical difficulty in developing VCMRAM. Heavily damped precessional switching is a writing scheme for VCMRAM with a substantially high tolerance of pulse width although the minimum WER has been much higher than that of conventional dynamic switching with an optimum pulse width. In this study, we theoretically investigate the effect of MTJ shape and the direction of the applied magnetic field on the WER of heavily damped precessional switching. The results show that the WER in elliptical-cylinder MTJ can be several orders of magnitude smaller than that in usual circular-cylinder MTJ when the external magnetic field is applied parallel to the minor axis of the ellipse. The reduction in WER is due to the fact that the demagnetization field narrows the component of the magnetization distribution perpendicular to the plane direction immediately before the voltage is applied.