Nanotube diameter optimal for channeling of high-energy particle beam

Abstract

Channeling of particle beam in straight and bent single-wall nanotubes has been studied in computer simulations. We have found that the nanotubes should be sufficiently narrow in order to steer efficiently the particle beams, with preferred diameter in the order of 0.5-2 nm. Wider nanotubes, e.g. 10-50 nm, appear rather useless for channeling purpose because of high sensitivity of channeling to nanotube curvature. We have compared bent nanotubes with bent crystals as elements of beam steering technique, and found that narrow nanotubes have an efficiency of beam bending similar to that of crystals.

Studies of nanotube channeling for efficient beam scraping at accelerators

“…The particles were tracked through the curved lattice of nanotubes in the approach with a continuous potential described in more detail elsewhere [32]. We varied nanotube parameters such as the length, diameter, bending, alignment angle, and the structure: either SWNT or MWNT.…”

Angular distributions of high energy protons channeled in long (10,10) single-wall carbon nanotubes

“…After that, a number of theoretical groups have studied ion channeling in carbon nanotubes [7][8][9][10][11][12]. Greenenko and Shulga investigated in detail the motion of channeled protons in a bundle of (10, 10) single-wall carbon nanotubes (SWCNTs) [13].…”

Creating microbeams and nanobeams by channeling in micro- and nano-structures

“…While crystal channeling is a well-established technique, nanotube channeling is just emerging as a beam instrument [9][10][11][12][13]. Here, beam can be trapped in a single nanotube cylinder of ≈1 nm diameter or in a rope consisting of many nanotubes.…”

“…We have developed a Monte Carlo code and done simulations of particle channeling in bent single-wall nanotubes, aimed at finding how useful nanotubes are for channeling of positively-charged particle beams, what kind of nanotubes are efficient for this job, and how nanotubes compare with crystals in this regard [12]. Figure 3 shows how the number of 1 GeV protons channeled through 50-µm-long nanotube depends on nanotube curvature pv/R for tubes of different diameters.…”

“…A lifetime of ~5·10 20 proton irradiation per cm 2 as measured [14] for channeling crystal corresponds to 5·10 12 /µm 2 ; this means over 100 years of operation of 1-µm 2 crystal with channeling of ~1000 protons/s, or one year for (20-nm) 2 nano-rope operating at 100 protons/s.…”