Single carbon-nanotube photonics and optoelectronics

Single-walled carbon nanotubes have unique optical properties as a result of their one-dimensional structure. Not only do they exhibit strong polarization for both absorption and emission, large exciton binding energies allow for room-temperature excitonic luminescence. Furthermore, their emission is in the telecom-wavelengths and they can be directly synthesized on silicon substrates, providing new opportunities for nanoscale photonics and optoelectronics. Here we discuss the use of individual single-walled carbon nanotubes for generation, manipulation, and detection of light on a chip. Their emission properties can be controlled by coupling to silicon photonic structures such as photonic crystal microcavities [1] and microdisk resonators [2]. Simultaneous photoluminescence and photocurrent measurements show that excitons can dissociate spontaneously [3], enabling photodetection at low bias voltages despite the large binding energies. More recently, we have found that alternating gate-voltages can generate optical pulse trains from individual nanotubes [4]. Ultimately, these results may be combined to achieve further control over photons at the nanoscale. \\[4pt] [1] R. Miura, S. Imamura, R. Ohta, A. Ishii, X. Liu, T. Shimada, S. Iwamoto, Y. Arakawa, and Y. K. Kato, Nature Commun. 5, 5580 (2014). \\[0pt] [2] S. Imamura, R. Watahiki, R. Miura, T. Shimada, and Y. K. Kato, Appl. Phys. Lett. 102, 161102 (2013). \\[0pt] [3] Y. Kumamoto, M. Yoshida, A. Ishii, A. Yokoyama, T. Shimada, and Y. K. Kato, Phys. Rev. Lett., 112, 117401 (2014). \\[0pt] [4] M. Jiang, Y. Kumamoto, A. Ishii, M. Yoshida, T. Shimada, and Y. K. Kato, arXiv:1407.7086.