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arXiv · 1710.05792

Carrier and Spin Coherent Dynamics in Strained Germanium-Tin Semiconductor on Silicon

Sebastiano De Cesari·Andrea Balocchi·Elisa Vitiello·Pedram Jahandar·Emanuele Grilli·Thierry Amand·Xavier Marie·Maksym Myronov·Fabio Pezzoli
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Abstract

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.

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Sebastiano De Cesari, Andrea Balocchi, Elisa Vitiello, Pedram Jahandar, Emanuele Grilli, Thierry Amand, Xavier Marie, Maksym Myronov, Fabio Pezzoli. 2017-10-16. Carrier and Spin Coherent Dynamics in Strained Germanium-Tin Semiconductor on Silicon. https://doi.org/10.1103/physrevb.99.035202

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