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arXiv · 1903.02113

Controlling magnetoresistance by oxygen impurities in Mq3-based molecular spin valves

Alberto Riminucci·Zhi-Gang Yu·Mirko Prezioso·Raimondo Cecchini·Ilaria Bergenti·Patrizio Graziosi·Valentin Alek Dediu
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Abstract

The understanding of magnetoresistance (MR) in organic spin valves (OSVs) based on molecular semiconductors is still incomplete after its demonstration more than a decade ago. While carrier concentration may play an essential role in spin transport in these devices, direct experimental evidence of its importance is lacking. We probed the role of charge carrier concentration by studying the interplay between MR and multilevel resistive switching in OSVs. The present work demonstrates that all salient features of these devices, particularly the intimate correlation between MR and resistance, can be accounted for by the impurity band model, based on oxygen migration. Finally, we highlight the critical importance of carrier concentration in determining spin transport and MR in OSVs and the role of interface-mediated oxygen migration in controlling the OSVs response.

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Alberto Riminucci, Zhi-Gang Yu, Mirko Prezioso, Raimondo Cecchini, Ilaria Bergenti, Patrizio Graziosi, Valentin Alek Dediu. 2019-03-05. Controlling magnetoresistance by oxygen impurities in Mq3-based molecular spin valves. https://doi.org/10.1021/acsami.8b20423

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