The optical properties of the carbon di-vacancy-antisite complex in the light of the TS photoluminescence center
Sprache des Vortragstitels:
Englisch
Original Tagungtitel:
International Confrence on Silicon Carbide and related Materials 2022
Sprache des Tagungstitel:
Englisch
Original Kurzfassung:
SiC hosts color centers, such as the silicon vacancy (VSi), the
divacancy (VSiVC), and the carbon antisitevacancy complex (CSiVC) that
are relevant quantum bits and single photon sources for quantum
technology [1-3]. The high potential of vacancy-related centers urges
to further explore this class of defects. The carbon di-vacancy-antisite
complex (VCCSiVC) was earlier suggested as an annealing product of the
divacancy (via conversion of VSi) [4, 5] and of CSiVC (via the
attachment of VC) [5] and therefore is expected to be a relevant defect.
The theoretical investigation of this center and its photo physics is a
requisite for a pending identification in experiments. Indeed, the
presence of carbon and silicon dangling bonds as in CSiVC suggests rich
photo and spin physics that has not yet been explored. Recently, we
identified a novel thermally stable TS center in photoluminescence (PL)
experiments [6]. This PL center consists of a set of three lines TS1,
TS2, and TS3 with a strong response to electric fields (Stark shift) and
strain [7]. Its capability to emit single photons makes this center
promising. Thermal annealing enhances the intensity of the PL center at
temperatures at which the PL lines of CSiVC and VSiVC disappear,
indicating that this center may be a common annealing product. In this
work we combine our experimental and theoretical approaches and
investigate the photophysical properties of the TS center and VCCSiVC
in 4H-SiC with the aim to unravel the supposed relation between them.
Our theoretical approach based on hybrid density functional theory (DFT)
reveals the groundstate properties of the four inequivalent
configurations of VCCSiVC realized in 4H-SiC....
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