When annealing a 4H silicon carbide (SiC) crystal, a sequence of optically active defect centers occurs among which the TS center is a prominent example. Here, we present low-temperature photoluminescence analyses on the single defect level. They reveal that the three occurring spectral signatures TS1, TS2 and TS3 originate from one single defect. Their polarization dependences expose three different crystallographic orientations in the basal plane, which relate to the projections of the nearest neighbor directions. Accordingly, we find a three-fold level-splitting in ensemble studies, when applying mechanical strain. This dependency is quantitatively calibrated. A complementary electrical measurement, deep level transient spectroscopy, reveals a charge transition level of the TS defect at 0.6 eV above the valence band. For a future identification, this accurate characterization of its optical and electronic properties along with their response to mechanical strain is a milestone.
@article{arxiv.2404.09618,
title = {On the experimental properties of the TS defect in 4H-SiC},
author = {Johannes A. F. Lehmeyer and Alexander D. Fuchs and Zhengming Li and Titus Bornträger and Fabio Candolfi and Maximilian Schober and Marcus Fischer and Martin Hartmann and Elke Neu and Michel Bockstedte and Michael Krieger and Heiko B. Weber},
journal= {arXiv preprint arXiv:2404.09618},
year = {2024}
}