Plasmon mediated light emission from metallic clusters through electron injection from carbon nanotube tips.

Aligned carbon nanotube arrays on flexible substrates can be used as a basis for various applications, including novel display technologies. In this context, we consider a system consisting of a spherical metallic cluster attached to the tip of a straight carbon nanotube. In the field emission configuration, electrons injected into the cluster can generate efficiently plasma oscillations, which in turn emit radiation at the plasma frequency, tunable by particle size and choice of metal. We investigate here the electrostatic potential profile at the nanotube-cluster junction employing the local density approximation. We also calculate the electron-plasmon scattering rate as a function of the injected electron energy, using the random phase approximation (RPA). Finally, we calculate the plasmon-photon conversion rates within the RPA. Results of our calculations show that this system is a promising candidate for nanotube based high resolution light sources.