Issue 22, 2022

Room-temperature magnetoresistance in Ni78Fe22/C8-BTBT/Ni78Fe22 nanojunctions fabricated from magnetic thin-film edges using a novel technique

Abstract

Molecular spintronic devices are gaining popularity because the organic semiconductors with long spin relaxation times are expected to have long spin diffusion lengths. A typical molecular spintronic device consists of organic molecules sandwiched between two magnetic layers, which exhibits magnetoresistance (MR) effect. Nanosized devices are also expected to have a high spin polarization, leading to a large MR effect owing to effective orbital hybridization. However, most studies on nanosized molecular spintronic devices have investigated the MR effect at low temperatures because of the difficulty in observing the MR effect at room temperature. Here we focus on high-mobility molecules expected to show long spin diffusion lengths, which lead to the observation of the MR effect in nanoscale junctions at room temperature. In this study, we fabricate magnetic nanojunctions consisting of high-mobility molecules, 2,7-dioctyl[1]benzothieno[3,2-b][1]benzothiophene (C8-BTBT), sandwiched between two Ni78Fe22 thin films with crossed edges. Transmission electron microscopy (TEM) images reveal that C8-BTBT molecular layers with smooth and clear interfaces can be deposited on the Ni78Fe22 thin-film edges. Consequently, we observe a clear positive MR effect, that is, RP < RAP, where RP and RAP are the resistances in the parallel (P) and antiparallel (AP) configurations, respectively, of two magnetic electrodes in the Ni78Fe22/C8-BTBT/Ni78Fe22 nanojunctions at room temperature. The obtained results indicate that the spin signal through the C8-BTBT molecules can be successfully observed. The study presented herein provides a novel nanofabrication technique and opens up new opportunities for research in high-mobility molecular nano-spintronics.

Graphical abstract: Room-temperature magnetoresistance in Ni78Fe22/C8-BTBT/Ni78Fe22 nanojunctions fabricated from magnetic thin-film edges using a novel technique

Supplementary files

Article information

Article type
Paper
Submitted
07 Jul 2022
Accepted
04 Oct 2022
First published
12 Oct 2022
This article is Open Access
Creative Commons BY-NC license

Nanoscale Adv., 2022,4, 4739-4747

Room-temperature magnetoresistance in Ni78Fe22/C8-BTBT/Ni78Fe22 nanojunctions fabricated from magnetic thin-film edges using a novel technique

M. Matsuzaka, Y. Sasaki, K. Hayashi, T. Misawa, T. Komine, T. Akutagawa, M. Fujioka, J. Nishii and H. Kaiju, Nanoscale Adv., 2022, 4, 4739 DOI: 10.1039/D2NA00442A

This article is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported Licence. You can use material from this article in other publications, without requesting further permission from the RSC, provided that the correct acknowledgement is given and it is not used for commercial purposes.

To request permission to reproduce material from this article in a commercial publication, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party commercial publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements