Germanium-Tin is emerging as a material exhibiting excellent photonic properties. Here we demonstrate optical initialization and readout of spins in this intriguing group IV semiconductor alloy and report on spin quantum beats between Zeeman-split levels under an external magnetic field. Our optical experiments reveal robust spin orientation in a wide temperature range and a persistent spin lifetime that approaches the ns regime at room temperature. Besides important insights into nonradiative recombination pathways, our findings disclose a rich spin physics in novel epitaxial structures directly grown on a conventional Si substrate. This introduces a viable route towards the synergic enrichment of the group IV semiconductor toolbox with advanced spintronics and photonic capabilities.
@article{arxiv.1710.05792,
title = {Carrier and Spin Coherent Dynamics in Strained Germanium-Tin Semiconductor on Silicon},
author = {Sebastiano De Cesari and Andrea Balocchi and Elisa Vitiello and Pedram Jahandar and Emanuele Grilli and Thierry Amand and Xavier Marie and Maksym Myronov and Fabio Pezzoli},
journal= {arXiv preprint arXiv:1710.05792},
year = {2019}
}