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arXiv · 2605.29492

Near surface donor-acceptor pairs in hydrogenated homoepitaxial diamond nanolayers

A. M. Romshin·A. P. Bolshakov·A. A. Zhivopistsev·A. V. Gritsienko·O. S. Kudryavtsev·P. A. Pivovarov·V. G. Ralchenko·I. I. Vlasov
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Abstract

Hydrogen-terminated diamond is known for its p-type surface conductivity, which arises from a near-surface hole accumulation layer induced by adsorbed acceptor species. Here, we demonstrate that these surface acceptors also form optically active donor-acceptor pairs (DAP) with substitutional nitrogen donors in diamond. The insertion of a nominally undoped CVD interlayer between a nitrogen-rich HPHT substrate and a hydrogen-terminated surface enables the precise tuning of the donor-acceptor separation with nanometer precision. Radiative DAP recombination appears as bright, spectrally narrow lines whose intensity, energy, and decay dynamics depend systematically on interlayer thickness. Individual lines show single-photon statistics, while ensembles exhibit strong polarization anisotropy reflecting the planar donor-acceptor geometry. These findings reveal an optical counterpart of hydrogen-induced surface transfer doping in diamond and establish a surface-defined, nanometer-tunable platform for engineering DAP-based quantum emitters.

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A. M. Romshin, A. P. Bolshakov, A. A. Zhivopistsev, A. V. Gritsienko, O. S. Kudryavtsev, P. A. Pivovarov, V. G. Ralchenko, I. I. Vlasov. 2026-05-28. Near surface donor-acceptor pairs in hydrogenated homoepitaxial diamond nanolayers. https://arxiv.org/abs/2605.29492

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