2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/19234The nonlinear capacitance in doped nanotube junctions is calculated self consistently. It decreases as a function of the applied bias when the latter becomes larger than the pseudogap of the nanotube. For this device, one can deduce a relaxation time of about 0.1 femtosecond. Because of its negative differential resistance (NDR), a switching time of less than a fs can also be deduced.Letter with 3 .ps figuresMaterials ScienceMesoscale and Nanoscale Physicstext