Laser induced spin injection to [GeTe/Sb2Te3] superlattice through a TbFeCo film

A [GeTe/Sb2Te3] superlattice is known as a topological insulator and it shows magnetic responses such as magneto-optical effect although it does not contain any magnetic element. We reported the superlattice has topologically protected spin diffusion length more than 100 mu m at room temperature. In this paper, we show a laser induced spin injection to the superlattice using a TbFeCo film. We got spin injection signals between the TbFeCo and the Pt bars through the superlattice without electric current. The signals showed the maximum value of 0.06 mu V around laser power of 1.0 mW which was focused to a spot diameter of 0.7 mu m. The laser induced spin injection method will be one of the useful methods for future low-energy spintronics devices. (c) 2022 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/). https://doi.org/10.1063/9.0000300

Automated summary

In this study, we report the experimental results of a [GeTe/Sb2Te3] superlattice with a topologically protected spin diffusion length exceeding 100 μm at room temperature. By using a TbFeCo film for laser-induced spin injection into the superlattice, we successfully obtained spin injection signals between TbFeCo and Pt bars without electric current. This research provides a useful method for future low-energy spintronics devices.