Electronic transport in individual carbon nanotube bundles under pressure
Résumé
Field-effect transistors based on individual carbon nanotubes with reduced Schottky barriers are studied up to pressures of 0.9 GPa and down to temperatures of less than 10 K. At ambient temperature and high pressure, complex effects are observed in a small bundle of tubes stemming from either the intrinsic modifications of the nanotubes at their ovalization, the evolution of barriers at the tube/electrodes contacts, or even both processes. Variations of the nanotube transport characteristics related to changes in the tube environment are most possibly also involved. Despite the highly complex pressure induced changes occurring in our device, low temperature measurements (<10 K) at high pressure (4.5 kbar) provide the first experimental evidence of Coulomb blockade at high pressure and the conservation of the ballistic behaviour of charges carriers in nanotubes under important stress-induced strain.