Photoluminescence of Nitrogen-Vacancy Centers by Ultraviolet One- and Two-Photon Excitation of Fluorescent Nanodiamonds
Fluorescent nanodiamonds contain nitrogen-vacancy (NV) centers as quantum defects. When exposed to a continuous-wave 325 nm laser or a femtosecond 344 nm laser, the particles emit red fluorescence from NV0 centers at ∼620 nm. Power dependence measurements of the emission strength revealed a predomin...
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Published in | The journal of physical chemistry letters Vol. 13; no. 48; pp. 11280 - 11287 |
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Main Authors | , , , , , , |
Format | Journal Article |
Language | English |
Published |
United States
American Chemical Society
08.12.2022
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Subjects | |
Online Access | Get full text |
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Summary: | Fluorescent nanodiamonds contain nitrogen-vacancy (NV) centers as quantum defects. When exposed to a continuous-wave 325 nm laser or a femtosecond 344 nm laser, the particles emit red fluorescence from NV0 centers at ∼620 nm. Power dependence measurements of the emission strength revealed a predominantly linear behavior at the laser peak intensity lower than 1 GW·cm–2, contributed mainly by photoexcitation of electrons from the valence band of diamond to the NV0 centers, followed by relaxation via electron–hole recombination. In the higher power regions, however, nonresonant two-photon interband excitation of the diamond matrix dominates the photoluminescence processes. Best fits of the experimental data to semiempirical models revealed an ionization coefficient of ∼1 cm–1 for the one-photon valence-to-defect excitation and a saturation intensity of 180 ± 60 GW·cm–2 for the two-photon interband excitation. The study provides new insight into the photoionization of NV0 centers and the interband excitation properties of diamond in the UV region. |
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Bibliography: | ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23 |
ISSN: | 1948-7185 1948-7185 |
DOI: | 10.1021/acs.jpclett.2c03064 |