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Spin‐dependent pair generation at Si/SiO2 interfaces

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Abstract

We report spin‐dependent generation of electron‐hole pairs at the Si/SiO 2 interface detected via microwave‐induced changes in the recombination current through a gate‐controlled diode.

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... This is the reason why signals of strongly coupled spin pairs in principle should not be detectable with EDMR. Only if intersystem crossing (ISC) [31] from the triplet to the singlet manifold is made possible by, e.g., spin-orbit coupling (SOC) [32,33] or if a third spin is involved in the spin-dependent process [34], singlet pair population is generated and the induced current change can be observed as an EDMR signal. ...
... Here, SOC can play an important role. Alternatively, coupling to an additional spin which goes along with coupled spin states could promote triplet-to-singlet conversion, as already suggested for other systems [10,34]. The additional spin needs to be spatially close to the TE spin to achieve a sufficiently strong interaction. ...
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