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arXiv · 2501.11481

Nitrogen-Vacancy Centers in Epitaxial Laterally Overgrown Diamond: Towards Up-scaling of Color Center-based Quantum Technologies

Nimba Oshnik·Sebastian Westrich·Nina Burmeister·Oliver Roman Opaluch·Lahcene Mehmel·Riadh Issaoui·Alexandre Tallaire·Ovidiu Brinza·Jocelyn Achard·Elke Neu
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Abstract

Providing high-quality, single-crystal diamond (SCD) with a large area is desirable for up-scaling quantum technology applications that rely on color centers in diamond. Growth methods aiming to increase the area of SCD are an active research area. Native color centers offer a sensitive probe for local crystal quality in such novel materials e.g., via their reaction to stress. In this work, we investigate individual native nitrogen-vacancy (NV) centers in SCD layers manufactured via laterally overgrowing hole arrays in a heteroepitaxially grown large-scale substrate. Heteroepitaxy has become a common tool for growing large SCDs; however, achieving the high crystal quality needed for quantum applications remains a challenge. In the overgrown layer, we identify NV centers with spin-decoherence times in the order of hundreds of microseconds, comparable to high-purity homoepitaxial SCD. We quantify the effective crystal strain in different regions of the overgrown layer, indicating a low stress overall and a stress reduction in the diamond layer above the holes.

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Nimba Oshnik, Sebastian Westrich, Nina Burmeister, Oliver Roman Opaluch, Lahcene Mehmel, Riadh Issaoui, Alexandre Tallaire, Ovidiu Brinza, Jocelyn Achard, Elke Neu. 2025-01-20. Nitrogen-Vacancy Centers in Epitaxial Laterally Overgrown Diamond: Towards Up-scaling of Color Center-based Quantum Technologies. https://doi.org/10.1088/2633-4356%2Fadce50

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