Nanotube and Graphene Cavity Photonics

We study the light-matter interaction by tuning the photonic environment of carbon nanotube and graphene electronic devices. Our approach is to integrate functional carbon nanotube and graphene devices into a planar optical microresonator cavity. In such a cavity the confinement of light in one or more dimensions alters the photonic density of states dramatically as compared to the free space. The confinement provided by the cavity completely determines what modes of the electromagnetic field are allowed/forbidden which for example can lead to selective enhancement/inhibition of emission/absorption.

Monolithic Integration of Nanotube Devices

For the integration of devices into an optical microresonator cavity, the standard silicon substrate has to be replaced by a material which is suitable as an intracavity medium. We have chosen to work with 50 nm thin silicon nitride membranes as low loss dielectric material. On such membranes devices are prepared by the dielectrophoretic assembling technique, which allows to assemble sorted carbon nanotubes or graphene in desired locations on the target substrate [1,2]. A second intracavity medium, Al₂O₃, on top of the devices in combination with two mirrors allows for easy tuning of the cavity resonance over the visible wavelength range. Sorted nanotubes are synthesized in subproject C3.2.