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arXiv · 2608.30790

Fine structure of the M-center in Si

Aurora Teien·David R. Gongora·Arnulf Johannes Snedker-Nielsen·Viktor Bobal·Augustinas Galeckas·Peter Granum·Stefano Paesani·Marianne Etzelmüller Bathen·Lasse Vines
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Abstract

Color centers in silicon offer great possibilities for scalable quantum technologies. The M-center, proposed to originate from a carbon-hydrogen complex, offers telecommunications-band emission and a paramagnetic ground state similar to the T-center. Here, we report on photoluminescence lines in the vicinity of the M-center and investigate their properties, including their dependence on temperature, implantation fluence, implantation isotope, and annealing temperature. Three emission lines are observed that are blue-shifted by 1.1, 2.8 and 3.6 meV relative to the 761 meV zero phonon line of the M center, where the 2.8 meV line exhibits negative thermal quenching and is therefore proposed to originate from a second excited state of the M-center. The remaining blue-shifted emission lines, together with two additional red-shifted (4.7 and 6.4 meV) emission lines display normal thermal quenching, and are unaffected by an isotope shift of the implanted carbon atom ($^{12}$C versus $^{13}$C implantation) and implantation fluence. Thus, they likely arise either from other defects with similar emission energies or from a perturbed configuration of the M-center.

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Aurora Teien, David R. Gongora, Arnulf Johannes Snedker-Nielsen, Viktor Bobal, Augustinas Galeckas, Peter Granum, Stefano Paesani, Marianne Etzelmüller Bathen, Lasse Vines. 2026-08-31. Fine structure of the M-center in Si. https://arxiv.org/abs/2608.30790

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