Many biological devices exhibit activated responses under various stimuli, and one such behavior is the mechano-transduction channels involved for instance in touch sensing or ear hair cells. In the present paper, we show that tiny (single digit) carbon nanotubes, with a radius of 2nm, do exhibit a mechano-sensitive response, which is furthermore very similar to that of their biological counterpart, with the conductance of the CNT exhibiting a strong and quadratic dependence on the applied pressure.
We can even rationalize this behavior theoretically with an analytical prediction for the pressure-dependent conductance. This demonstrates, incidentally, that the mechano-sensitive response takes its root in the ultra-low friction exhibited by carbon nanotube with the smallest size. This demonstrates the further uniqueness of carbon nanotubes materials as water and ion transporters. We exploit here its unique properties to induce non-linear, stimulated transport.
reference
Alice Marcotte et al. Mechanically activated ionic transport across single-digit carbon nanotubes, Nature Materials (2020). DOI: 10.1038/s41563-020-0726-4