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arXiv · 2001.02749

Giant shift upon strain on the fluorescence spectrum of V$_{\rm N}$N$_{\rm B}$ color centers in $h$-BN

Song Li·Jyh-Pin Chou·Alice Hu·Martin B. Plenio·Péter Udvarhelyi·Gergő Thiering·Mehdi Abdi·Adam Gali
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Abstract

We study the effect of strain on the physical properties of the nitrogen antisite-vacancy pair in hexagonal boron nitride ($h$-BN), a color center that may be employed as a quantum bit in a two-dimensional material. With group theory and ab-initio analysis we show that strong electron-phonon coupling plays a key role in the optical activation of this color center. We find a giant shift on the zero-phonon-line (ZPL) emission of the nitrogen antisite-vacancy pair defect upon applying strain that is typical of $h$-BN samples. Our results provide a plausible explanation for the experimental observation of quantum emitters with similar optical properties but widely scattered ZPL wavelengths and the experimentally observed dependence of the ZPL on the strain.

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Song Li, Jyh-Pin Chou, Alice Hu, Martin B. Plenio, Péter Udvarhelyi, Gergő Thiering, Mehdi Abdi, Adam Gali. 2020-01-08. Giant shift upon strain on the fluorescence spectrum of V$_{\rm N}$N$_{\rm B}$ color centers in $h$-BN. https://doi.org/10.1038/s41534-020-00312-y

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