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Tunable room-temperature single-photon emission at telecom wavelengths from sp3 defects in carbon nanotubes


Generating quantum light emitters that operate at room temperature and at telecom wavelengths remains a significant materials challenge. To achieve this goal requires light sources that emit in the near-infrared wavelength region and that, ideally, are tunable to allow desired output wavelengths to be accessed in a controllable manner. Here, we show that exciton localization at covalently introduced aryl sp3 defect sites in single-walled carbon nanotubes provides a route to room-temperature single-photon emission with ultrahigh single-photon purity (99%) and enhanced emission stability approaching the shot-noise limit. Moreover, we demonstrate that the inherent optical tunability of single-walled carbon nanotubes, present in their structural diversity, allows us to generate room-temperature single-photon emission spanning the entire telecom band. Single-photon emission deep into the centre of the telecom C band (1.55 µm) is achieved at the largest nanotube diameters we explore (0.936 nm).

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Figure 1: Illustration of exciton localization and wavelength-tunable defect-state emission (E11* and E11*) in aryl-functionalized SWCNTs of varying (n,m).
Figure 2: Photoluminescence characteristics and photon antibunching properties of sp3 defect-state emission (E11* and E11*) from aryl-functionalized (6,5), (7,5) and (10,3) SWCNTs.
Figure 3: Global trends in single-photon emission statistics and dynamics over the complete range of SWCNT (n,m) and observed E11* emission wavelengths.


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This work was conducted in part at the Center for Integrated Nanotechnologies, a US Department of Energy, Office of Science user facility and supported in part by Los Alamos National Laboratory Directed Research and Development funds. This effort was also supported at AIST in part by the Japan Society for the Promotion of Science (JSPS) KAKENHI grant numbers JP16H07103 and JP25220602. National Renewable Energy Laboratory (NREL) researchers were supported by the Solar Photochemistry Program of the US Department of Energy, Office of Science, Basic Energy Sciences, Division of Chemical Sciences, Geosciences and Biosciences, under contract no. DE-AC36-08GO28308 to NREL. W.G. and J.K. acknowledge support from the Robert A. Welch Foundation through grant no. C-1509.

Author information




H.H. and S.K.D. conceived and designed the experiment. X.H., under the supervision of H.H. and S.K.D. and with assistance from X.M. and Y.K., performed all spectroscopy studies and data analysis and, with N.F.H. under the supervision of S.K.D., performed nanotube separation and functionalization. R.I. and J.L.B. provided PFO-bpy-wrapped (6,5) SWCNT material. Y.Y., A.H., T.T., H.K., W.G. and J.K. provided (10,3) SWCNT material. X.H., H.H. and S.K.D. prepared the manuscript with assistance from all other co-authors.

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Correspondence to Han Htoon or Stephen K. Doorn.

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The authors declare no competing financial interests.

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He, X., Hartmann, N., Ma, X. et al. Tunable room-temperature single-photon emission at telecom wavelengths from sp3 defects in carbon nanotubes. Nature Photon 11, 577–582 (2017).

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