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arXiv · 2209.05073

Interface-Assisted Room-Temperature Magnetoresistance in Cu-Phenalenyl-based Magnetic Tunnel Junctions

Neha Jha·Anand Paryar·Tahereh Sadat Parvini·Christian Denker·Pavan K. Vardhanapu·Gonela Vijaykumar·Arne Ahrens·Michael Seibt·Jagadeesh S. Moodera·Swadhin K. Mandal·Markus Münzenberg
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Abstract

Delocalized carbon-based radical species with unpaired spin, such as phenalenyl (PLY) radical, opened avenues for developing multifunctional organic spintronic devices. Here we develop a novel technique based on a three-dimensional shadow mask and the in-situ deposition to fabricate PLY-, Cu-PLY-, and Zn-PLY-based organic magnetic tunnel junctions (OMTJs) with area 3x8 {\mu}m2 and improved morphology. The nonlinear and weakly temperature-dependent current-voltage (I-V) characteristics in combination with the low organic barrier height suggest tunneling as the dominant transport mechanism in the structurally and dimensionally optimized OMTJs. Cu-PLY-based OMTJs, show a significant magnetoresistance up to 14 percent at room temperature due to the formation of hybrid states at the metal-molecule interfaces called spinterface, which reveals the importance of spin-dependent interfacial modification in OMTJs design. In particular, Cu-PLY OMTJs shows a stable voltage-driven resistive switching response that suggests their use as a new viable and scalable platform for building molecular scale quantum memristors and processors.

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Neha Jha, Anand Paryar, Tahereh Sadat Parvini, Christian Denker, Pavan K. Vardhanapu, Gonela Vijaykumar, Arne Ahrens, Michael Seibt, Jagadeesh S. Moodera, Swadhin K. Mandal, Markus Münzenberg. 2022-09-12. Interface-Assisted Room-Temperature Magnetoresistance in Cu-Phenalenyl-based Magnetic Tunnel Junctions. https://arxiv.org/abs/2209.05073

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