El Abbassi, MariaMariaEl AbbassiPerrin, Mickael L.Mickael L.PerrinBarin, Gabriela BorinGabriela BorinBarinSangtarash, SaraSaraSangtarashOverbeck, JanJanOverbeckBraun, OliverOliverBraunLambert, Colin J.Colin J.LambertSun, QiangQiangSunPrechtl, ThorstenThorstenPrechtlNarita, AkimitsuAkimitsuNaritaMüllen, KlausKlausMüllenRuffieux, PascalPascalRuffieuxSadeghi, HatefHatefSadeghiFasel, RomanRomanFaselCalame, MichelMichelCalame2024-09-022024-09-022020https://boris-portal.unibe.ch/handle/20.500.12422/37023Graphene nanoribbons (GNRs) have attracted strong interest from researchers worldwide, as they constitute an emerging class of quantum-designed materials. The major challenges toward their exploitation in electronic applications include reliable contacting, complicated by their small size (<50 nm), and the preservation of their physical properties upon device integration. In this combined experimental and theoretical study, we report on the quantum dot behavior of atomically precise GNRs integrated in a device geometry. The devices consist of a film of aligned five-atom-wide GNRs (5-AGNRs) transferred onto graphene electrodes with a sub 5 nm nanogap. We demonstrate that these narrow-bandgap 5-AGNRs exhibit metal-like behavior at room temperature and single-electron transistor behavior for temperatures below 150 K. By performing spectroscopy of the molecular levels at 13 K, we obtain addition energies in the range of 200-300 meV. DFT calculations predict comparable addition energies and reveal the presence of two electronic states within the bandgap of infinite ribbons when the finite length of the 5-AGNR is accounted for. By demonstrating the preservation of the 5-AGNRs' molecular levels upon device integration, as demonstrated by transport spectroscopy, our study provides a critical step forward in the realization of more exotic GNR-based nanoelectronic devices.en500 - Science::530 - Physics500 - Science::540 - Chemistryarticle10.7892/boris.1463253222325910.1021/acsnano.0c00604