Secondary electron interference from trigonal warping in clean carbon nanotubes Supplementary Material

As electrode material, a 10/40 nm Ti/Pt bilayer is patterned on top of a degenerately doped Si substrate with a 500 nm thick insulating capping layer, see Fig. S1. In order to avoid contamination of the CNT, we grow the carbon nanotube as a last fabrication step across the contact electrodes separated by a 1.2μm trench. The identification of a promising device is done solely via room temperature transport measurements using a probe station. This is necessary to avoid contamination of the nanotube. The transport measurements presented in the main text, Fig. 1, were recorded at a base temperature of 15 mK in a He/He dilution refrigerator. All data shown in the main text is recorded in a standard DC measurement setup, see schematics in Fig. S1. Voltage sources are connected to the source contact and to the doped substrate while the drain contact is grounded. The current is measured at the drain contact using a current-voltage converter. The conductance data is obtained by numerical derivation.