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Aspirations of modern high energy particle physics call for compact and cost efficient lepton and hadron colliders with energy reach and luminosity significantly beyond the modern HEP facilities. Strong interplanar fields in crystals of the order of 10−100 V/Å can effectively guide and collimate high energy particles. Besides continuous focusing crystals plasma, if properly excited, can be used for particle acceleration with exceptionally high gradients O(TeV/m). However, the angstrom-scale size of channels in crystals might be too small to accept and accelerate significant number of particles. Carbon-based nano-structures such as carbon-nanotubes (CNTs) and graphenes have a large degree of dimensional flexibility and thermo-mechanical strength and thus could be more suitable for channeling acceleration of high intensity beams. Nano-channels of the synthetic crystals can accept a few orders of magnitude larger phase-space volume of channeled particles with much higher thermal tolerance than natural crystals.

This paper presents conceptual foundations of the CNT acceleration, including underlying theory, practical outline and technical challenges of the proof-of-principle experiment. Also, an analytic description of the plasmon-assisted laser acceleration is detailed with practical acceleration parameters, in particular with specifications of a typical tabletop femtosecond laser system. The maximally achievable acceleration gradients and energy gains within dephasing lengths and CNT lengths are discussed with respect to laser-incident angles and the CNT-filling ratios.

Carbon nanotubes (CNTs) have attracted considerable interest because of their unique physical, electrical properties and many potential applications. Carbon nanotubes are considered to be the most promising candidate in electrode materials for secondary battery, solar cell and supercapacitor. Non-conductive substrates, such as silicon wafers have usually been used to synthesize CNTs. However, in applications such as electrodes, it is desirable to have CNTs grown on conductive buffer layer and conductive substrates. We researched the fabrication of carbon nanotubes on Ni/TiO₂/Ti substrate by Thermal chemical vapor deposition (TCVD). Experimental parameter is synthesis temperature, time and buffer layer thickness. The samples were characterized by means of field emission scanning electron microscopy (FE-SEM), Raman spectroscopy analysis, transmission electron microscope (TEM) and electrochemical test. The synthesized CNTs have the diameter of about 100~200 nm and the length of about 5~10 μm. Li/CNTs cell with CNTs on Ti substrate exhibited good charge/discharge behavior and slow capacity fading.