Research News

Polymer’s long spin relaxation time helps researchers gain spintronic insights

Multiple magnetic resonance techniques for spin currents

Measurements of spin currents in the hybrid interface of a device with a ferromagnetic (Py) layer and an organic semiconductor (PANI) layer.

Credit: Osaka Metropolitan University

Electrons spin even without an electric charge and this motion in condensed matter constitutes spin current, which is attracting a great deal of attention for next-generation technology such as memory devices. An Osaka Metropolitan University-led research group has been able to gain further insight into this important topic in the field of spintronics.

To investigate the characteristics of spin currents, OMU Graduate School of Science Professor Katsuichi Kanemoto’s group designed a multilayer device consisting of a ferromagnetic layer and an organic semiconductor material. By adopting a doped conducting polymer with a long spin relaxation time, the team succeeded in observing the effects of spin transport and spin current generation from the non-magnetic, organic semiconductor side.

The long spin relaxation times not only make for more efficiency in spintronics, but also enable direct observation of phenomena due to spin current generation in the organic layer side. Moreover, the researchers were able to find that, contrary to a theory that has been generally accepted, the width of the ferromagnetic resonance measurements for the layer of the spin current supplier slightly narrowed in the device system using the organic semiconductor with a long spin relaxation time.

“The use of the organic semiconductor makes it possible to pursue physical properties from the non-magnetic layer side, for which there was no information until now,” explained Professor Kanemoto. “Our work can be expected to contribute to a deeper understanding of the properties of spin currents.”

The findings were published in Advanced Electronic Materials.

Funding

This work was supported in part by the JSPS Kakenhi grant (numbers 19K22172 and 21H01906). We thank Idemitsu Kosan Co. Ltd., for generously providing PANI samples used in this study.

Paper information

Journal: Advanced Electronic Materials
Title: Spin Current Generation at the Hybrid Ferromagnetic Metal/Organic Semiconductor Interface as Revealed by Multiple Magnetic Resonance Techniques
DOI: 10.1002/aelm.202400322
Authors: Kohei Takaishi, Haruka Tsutsumi, Hideto Matsuoka, Takayuki Suzuki, Katsuichi Kanemoto
Published: 2 August 2024
URL: https://doi.org/10.1002/aelm.202400322

Contact

Katsuichi Kanemoto

Graduate School of Science
Email: kkane[at]omu.ac.jp

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