Tseng, PPTsengWEN-JENG HSUEH2020-03-102020-03-1020191367-2630https://scholars.lib.ntu.edu.tw/handle/123456789/475240© 2019 The Author(s). Published by IOP Publishing Ltd on behalf of the Institute of Physics and Deutsche Physikalische Gesellschaft. Pursuing larger tunnel magnetoresistance is a significant work to develop attractive spin-valve devices for high-performance read heads of hard disk drives, magnetic random access memories, and transistors. Here, we propose an ultra-giant magnetoresistance reaching higher than 40 000% at room temperature by using a spin valve of an armchair graphene nanoribbon with double gate-controlled potential barriers. The ultra-giant magnetoresistance approximately 60 times larger than that of traditional MgO-barrier spin valves is caused by an extraordinary current suppression in the antiparallel mode. Moreover, owing to the concept of the gate-voltage barrier, the proposed system provided not only lower complexity of the fabricating standard but also longer endurance of the operation than traditional spin-valve devices.spintronics; giant magnetoresistance; graphene spin transport; spin valve; graphene nanoribbonsjournal article10.1088/1367-2630/ab531f2-s2.0-85075775074WOS:000499454900001https://api.elsevier.com/content/abstract/scopus_id/85075775074