Ultra-Low Noise Measurements of Ionic Transport Within Individual Single-Walled Carbon Nanotubes
Résumé
Despite 15 years of extensive investigation, the fabrication and study of nanofluidic devices incorporating a single carbon nanotube (CNT) still represent a remarkable experimental challenge [1-3]. In this study, we present the fabrication of nanofluidic devices that integrate an individual single-walled CNT (SWCNT), showcasing a notable reduction in noise by 1-3 orders of magnitude compared to conventional devices. This achievement was made possible by employing high dielectric constant materials for both the substrate and the CNT-covering layer. Furthermore, we provide a detailed account of the crucial factors contributing to the successful fabrication of SWCNT-based nanofluidic devices that are reliably leak-free, plug-free, and long-lived. Key considerations include the quality of the substrate-layer interface, the nanotube opening, and the effective removal of photoresist residues and trapped microbubbles. We demonstrate that these devices, characterized by a high signal-to-noise ratio, enable spectral noise analysis of ionic transport through an individual SWCNT, thus showing that SWCNTs obey Hooge's law in 1/f at low frequencies [4]. Beyond advancing our fundamental understanding of ion transport in SWCNTs, these ultra-low noise measurements open avenues for leveraging SWCNTs in nanopore sensing applications for singlemolecule detection, offering high sensitivity and identification capabilities.
Domaines
Physique [physics]Origine | Fichiers produits par l'(les) auteur(s) |
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