TY - JOUR AB - We investigate electronic transport in n-i-n GaN nanowires with and without AlN double barriers. The nanowires are grown by catalyst-free, plasma-assisted molecular beam epitaxy enabling abrupt GaN/AlN interfaces as well as longitudinal n-type doping modulation. At low temperature, transport in n-i-n GaN nanowires is dominated by the Coulomb blockade effect. Carriers are confined in the undoped middle region, forming single or multiple islands with a characteristic length of ∼100 nm. The incorporation of two AlN tunnel barriers causes confinement to occur within the GaN dot in between. In the case of a 6 nm thick dot and 2 nm thick barriers, we observe characteristic signatures of Coulomb-blockaded transport in single quantum dots with discrete energy states. For thinner dots and barriers, Coulomb-blockade effects do not play a significant role while the onset of resonant tunneling via the confined quantum levels is accompanied by a negative differential resistance surviving up to ∼150 K. AU - Songmuang, Rudeeson AU - Georgios Katsaros AU - Monroy, Eva AU - Spathis, Panayotis N AU - Bougerol, Catherine AU - Mongillo, Massimo AU - De Franceschi, Silvano ID - 1753 IS - 9 JF - Nano Letters TI - Quantum transport in GaN/AlN double-barrier heterostructure nanowires VL - 10 ER -