Strong evidence for d-electron spin transport at room temperature at a LaAlO3/SrTiO3 interface

• DOI: 10.1038/nmat4857
• Publication Date: 2017-02-13T16:49:43Z
• Authors: Ryo Ohshima; Yuichiro Ando; Kosuke Matsuzaki; Tomofumi Susaki; Mathias Weiler; Stefan Klingler; Hans Huebl; Eiji Shikoh; Teruya Shinjo; Sebastian T. B. G...; Masashi Shiraishi
• Keywords: Condensed Matter - Materials Science; Quantum Physics; Condensed Matter - Mesoscale and Nanoscale Physics; Mesoscale and Nanoscale Physics (cond-mat.mes-hall); 500; Materials Science (cond-mat.mtrl-sci); FOS: Physical sciences; 540; Quantum Physics (quant-ph)

A d-orbital electron has an anisotropic electron orbital and is a source of magnetism. The realization of a 2-dimensional electron gas (2DEG) embedded at a LaAlO3/SrTiO3 interface surprised researchers in materials and physical sciences because the 2DEG consists of 3d-electrons of Ti with extraordinarily large carrier mobility, even in the insulating oxide heterostructure. To date, a wide variety of physical phenomena, such as ferromagnetism and the quantum Hall effect, have been discovered in this 2DEG systems, demonstrating the ability of the d-electron 2DEG systems to provide a material platform for the study of interesting physics. However, because of both ferromagnetism and the Rashba field, long-range spin transport and the exploitation of spintronics functions have been believed difficult to implement in the d-electron 2DEG systems. Here, we report the experimental demonstration of room-temperature spin transport in the d-electron-based 2DEG at a LaAlO3/SrTiO3 interface, where the spin relaxation length is ca. exceeding 200 nm. Our finding, which counters the conventional understandings to d-electron 2DEGs, opens a new field of d-electron spintronics. Furthermore, this work highlights a novel spin function in the conductive oxide system.<br/>30 pages, 5 Figures, 1 Table, including Supplemental Information<br/>