Semiconducting carbon nanotubes in optoelectronic and nanophotonic devices

The exciting optical and electronic properties of semiconducting carbon nanotubes are inspiring more and more demonstrations of their applicability in nanometer scale optoelectronics and photonics. Integrated in a device, however, the physical properties of carbon nanotubes are subject to strong modifications. The presence of dielectric substrates, external electric fields and electrostatic doping significantly alters the optical properties of carbon nanotubes [1, 2]. Also, charge carriers involved in electrical transport along carbon nanotubes excite non-equilibrium phonon populations and couple to surface polar phonons of a dielectric substrate [3]. As a result, the response of carbon nanotubes to external perturbations will ultimately determine the overall performance of a carbon nanotube device. By combining electrical measurements and optical micro-spectroscopy, it is possible to observe experimentally the different effects on the single nanotube level and elucidate the role of the various physical interactions that occur simultaneously in an operating carbon nanotube transistor. \\[4pt] [1] M. Steiner et al., Applied Physics A 96, 271-282 (2009) \\[0pt] [2] M. Steiner et al., Nano Letters 9, 3477-3481 (2009) \\[0pt] [3] M. Steiner et al., Nature Nanotechnology 4, 320-324 (2009)