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arXiv · 2601.04933

Long-lived state of a helium-like magnesium donor in silicon

R. Kh. Zhukavin·D. A. Postnov·P. A. Bushuikin·K. E. Kudryavtsev·K. A. Kovalevsky·V. V. Tsyplenkov·N. A. Bekin·A. N. Lodygin·L. M. Portsel·V. B. Shuman·Yu. A. Astrov·N. V. Abrosimov·V. N. Shastin
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Abstract

The relaxation of ortho states of a helium-like Mg donor in silicon is investigated by measuring the modulation of background radiation transmission through impurity centers under pulsed photoexcitation. Long-lived states of the spin-triplet 1s(3T2) group with a lifetime of about 20 ms are observed. The temperature dependence indicates that the relaxation is governed by the Orbach mechanism with an activation energy ~13 meV, which is close to the exchange splitting energy of the excited 1s states of the Mg donor.

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R. Kh. Zhukavin, D. A. Postnov, P. A. Bushuikin, K. E. Kudryavtsev, K. A. Kovalevsky, V. V. Tsyplenkov, N. A. Bekin, A. N. Lodygin, L. M. Portsel, V. B. Shuman, Yu. A. Astrov, N. V. Abrosimov, V. N. Shastin. 2026-01-08. Long-lived state of a helium-like magnesium donor in silicon. https://arxiv.org/abs/2601.04933

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