resumo
Vibronic coupling of color centers plays a crucial role in their effectiveness for quantum technologies. This study presents a novel approach to extract key parameters, including the Huang-Rhys factor and the one-phonon coupling function, from photoluminescence spectra containing the signal from multiple color centers. Monotonic splines are used to represent the one-phonon coupling function, optimized using a variable-length non-dominated sorting genetic algorithm. Our method is applied to the combination of the well-studied negatively charged nitrogen-vacancy center and its less explored neutral counterpart in diamond, observed through photoluminescence at 14 K. Despite the complexity inherent in the theoretical framework governing phonon coupling in photoluminescence, we achieve robust fits, yielding a normalized root-mean-squared error of approximately 6%. The neutral nitrogen-vacancy center exhibits a Huang-Rhys factor of 3.0, while its negatively charged counterpart showcases a value of 3.95. The quasi-localized vibrations of both charge states are clearly present in the fitted one-phonon spectral function. Furthermore, the consistency of our methodology is bolstered by temperature-dependent photoluminescence, which was calculated up to numerical constants using fit-derived parameters, matching the experimental measurements up to 300 K.
categoria
Optics
autores
Lamelas, A; Amaral, VS
nossos autores
Afonso Xavier de Matos Lamelas
Estudante de doutoramento
Vitor Brás Sequeira Amaral
Professor CatedráticoProjectos
CICECO - Aveiro Institute of Materials (UIDB/50011/2020)
CICECO - Aveiro Institute of Materials (UIDP/50011/2020)
Associated Laboratory CICECO-Aveiro Institute of Materials (LA/P/0006/2020)
agradecimentos
We specially thank Dr Joana Rodrigues and Dr Teresa Monteiro from i3N, Department of Physics, University of Aveiro, for the essential experimental training provided and access to their experimental setup which was used in the measurement shown. We acknowledge the funding from Fundacao para a Ciencia e Tecnologia through the 2022.11398.BD PhD studentship and the Project CERN/FIS-TEC/0003/2021. Moreover, this work was developed within the scope of the Project CICECO-Aveiro Institute of Materials, UIDB/50011/2020 (DOI 10.54499/UIDB/50011/2020), UIDP/50011/2020 (DOI 10.54499/UIDP/50011/2020) & LA/P/0006/2020 (DOI 10.54499/LA/P/0006/2020), financed by national funds through the FCT/MCTES (PIDDAC).