A high- TC heavy rare earth monoxide semiconductor TbO with a more than half-filled 4f orbital

Satoshi Sasaki; Daichi Oka; Kenichi Kaminaga; Daichi Saito; Taku Yamamoto; Nobuto Abe; Hirokazu Shimizu; Tomoteru Fukumura

doi:10.1039/d2dt02710k

A high- T_C heavy rare earth monoxide semiconductor TbO with a more than half-filled 4f orbital

Dalton Trans. 2022 Nov 8;51(43):16648-16652. doi: 10.1039/d2dt02710k.

Authors

Satoshi Sasaki¹, Daichi Oka¹, Kenichi Kaminaga², Daichi Saito¹, Taku Yamamoto¹, Nobuto Abe¹, Hirokazu Shimizu¹, Tomoteru Fukumura^{1

3

4

5}

Affiliations

¹ Department of Chemistry, Graduate School of Science, Tohoku University, Sendai 980-8578, Japan. tomoteru.fukumura.e4@tohoku.ac.jp.
² Department of Applied Chemistry, School of Engineering, Tohoku University, Sendai 980-8579, Japan.
³ Advanced Institute for Materials Research (WPI-AIMR) and Core Research Cluster, Tohoku University, Sendai 980-8577, Japan.
⁴ Center for Science and Innovation in Spintronics, Organization for Advanced Studies, Tohoku University, Sendai 980-8577, Japan.
⁵ Center for Spintronics Research Network, Tohoku University, Sendai 980-8577, Japan.

PMID: 36278476
DOI: 10.1039/d2dt02710k

Abstract

Terbium monoxide, TbO, with an unusual valence state of Tb²⁺ ([Xe]4f⁸5d¹) has been known to exist as a gas phase. In this study, we report a solid phase rock-salt structured TbO in the form of an epitaxial thin film. This TbO is a narrow gap ferromagnetic semiconductor with a bandgap of ∼0.1 eV and high Curie temperature of 231 K, and exhibited negative magnetoresistance of -14% at 9 T and 2 K. Its magnetization steeply increased with the appearance of a wasp-waisted hysteresis curve significantly below the Curie temperature at about 20 K. These results suggested that both 4f and 5d magnetic sublattices were formed at a single magnetic Tb²⁺ site in TbO.