Atomic defect color centers in solid-state systems hold immense potential to advance various quantum technologies. However, the fabrication of high-quality, densely packed defects presents a significant challenge. Herein we introduce a DNA-programmable photochemical approach for creating organic color-center quantum defects on semiconducting single-walled carbon nanotubes (SWCNTs). Key to this precision defect chemistry is the strategic substitution of thymine with halogenated uracil in DNA strands that are orderly wrapped around the nanotube. Photochemical activation of the reactive uracil initiates the formation of sp3 defects along the nanotube as deep exciton traps, with a pronounced photoluminescence shift from the nanotube band gap emission (by 191 meV for (6,5)-SWCNTs). Furthermore, by altering the DNA spacers, we achieve systematic control over the defect placements along the nanotube. This method, bridging advanced molecular chemistry with quantum materials science, marks a crucial step in crafting quantum defects for critical applications in quantum information science, imaging, and sensing.
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Engineering defects with DNA
Strategically introduced defects can be used to modify carbon nanotubes for new properties and functions. For example, chemical defects can act as atomic traps for electrons, holes, electron-hole pairs, and even molecules and ions ( 1 ). The ability to control the placement of these defects on carbon nanotubes could enable a plethora of fundamental studies and potential applications in imaging, sensing, disease diagnostics, and quantum information science ( 2 – 4 ). However, there is yet no effective way to do this with atomic precision ( 5 – 7 ). On page 535 of this issue, Lin et al. ( 8 ) report the creation of ordered defect arrays by programming DNA strands to wrap around and traverse the entire length of a single-walled carbon nanotube.
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- PAR ID:
- 10433093
- Date Published:
- Journal Name:
- Science
- Volume:
- 377
- Issue:
- 6605
- ISSN:
- 0036-8075
- Page Range / eLocation ID:
- 473 to 474
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1126/science.abq2580
