Deterministic Formation of Single Organic Color Centers in Carbon Nanotubes
#Quantum Emitter #Carbon Nanotube #Single Photon Source #Deterministic Functionalization #Telecom Wavelength #Quantum Photonics #Color Centers
Schematic diagram of quantum defect formation on carbon nanotube through photochemical reaction and excitation PL image showing the formed quantum defect.
Our research group has achieved the world’s first deterministic formation of single organic color centers in single-walled carbon nanotubes (SWCNTs). This breakthrough technique allows us to precisely control the number, position, and emission wavelength of quantum defects, opening new possibilities for quantum communication devices that operate at room temperature in the telecom wavelength range.
The key innovation lies in our deterministic single-molecule modification method, which monitors photochemical reactions in real-time and immediately halts the reaction when individual quantum defects form. This approach achieves unprecedented control over three critical parameters: limiting the number of quantum defects to exactly one, positioning them with sub-micron precision, and adjusting emission wavelength through carbon nanotube structure selection
Technical Approach
Our method employs continuous photoluminescence (PL) monitoring during the photochemical reaction process. When a single quantum defect forms, we detect its characteristic emission signal and immediately halt the chemical reaction within 500 milliseconds. This rapid response time is crucial for preventing the formation of multiple defects.
The photochemical reaction control system achieves single-molecule level detection sensitivity by monitoring discrete changes in photoluminescence intensity as individual organic color centers form on the nanotube. With a 77% success rate for forming single quantum defects and sub-micron spatial resolution, this technique represents a significant advancement in deterministic quantum emitter fabrication
Results and Performance
Photon correlation measurements reveal clear antibunching behavior with g^(2)(0) = 0.45, confirming the quantum nature of the color centers. These quantum emitters operate at room temperature and emit in the telecom wavelength range (1300-1600 nm), while demonstrating excellent photostability and single-photon emission characteristics.
Future Directions
Our current research focuses on integrating these quantum emitters with photonic circuits and improving the deterministic control to achieve success rates exceeding 90%. We are also extending this technique to other nanomaterial platforms and developing practical quantum communication devices for real-world applications
Publications
Nano Letters (2025): “Deterministic Formation of Single Organic Color Centers in Single-Walled Carbon Nanotubes” DOI: 10.1021/acs.nanolett.5c02378