All material supplied via Aaltodoc is protected by copyright and other intellectual property rights, and duplication or sale of all or part of any of the repository collections is not permitted, except that material may be duplicated by you for your research use or educational purposes in electronic or print form. You must obtain permission for any other use. Electronic or print copies may not ...

Single chlorophyll-a molecules, a vital resource for the sustenance of life on Earth, have been investigated by using scanning tunneling microscope manipulation and spectroscopy on a gold substrate at 4.6 K. Chlorophyll-a binds on Au(111) via its porphyrin unit while the phytyl-chain is elevated from the surface by the support of four CH(3) groups. By injecting tunneling electrons from the scan...

We investigate the atomic-scale tunneling characteristics of bilayer graphene on silicon carbide using the scanning tunneling microscopy. The high-resolution tunneling spectroscopy reveals an unexpected negative differential resistance (NDR) at the Dirac energy, which spatially varies within the single unit cell of bilayer graphene. The origin of NDR is explained by two near-gap van Hove singul...

In this paper, we have developed a model of the tunneling current through a highdielectric stack in MOS capacitors with anisotropic masses. The transmittance was numerically calculated by employing a transfer matrix method and including longitudinal-transverse kinetic energy coupling which is represented by an electron phase velocity in the gate. The transmittance was then applied to calculate ...

PACS. 73.63.-b – Electronic transport in mesoscopic or nanoscale materials and structures.. PACS. 73.23.Hk – Coulomb blockade; single-electron tunneling. PACS. 85.85.+j – Micro-and nano-electromechanical systems (MEMS/NEMS) and devices. Abstract. – Effects of a coupling between the mechanical vibrations of a quantum dot placed between the two leads of a single electron transistor and coherent t...

Single-stranded DNA was utilized as a probe tip for single-molecule DNA detection. Hybridization of the DNA tip and target DNA induces electron tunneling through the resulting DNA duplex. It is demonstrated that the DNA tip allows not only genetic detection but also discovery of single-nucleotide polymorphisms at the single-molecule level.

Electron tunneling through self-assembled monolayers of alkanethiols is investigated. Temperature-dependent current– voltage measurements are performed to distinguish between di erent conduction mechanisms. Temperature-independent electron transport is observed, proving direct tunneling as the dominant conduction mechanism of alkanethiols. An exponential dependence of tunneling current on molec...

We measure electron tunneling in transistors made from C(140), a molecule with a mass-spring-mass geometry chosen as a model system to study electron-vibration coupling. We observe vibration-assisted tunneling at an energy corresponding to the stretching mode of C(140). Molecular modeling provides explanations for why this mode couples more strongly to electron tunneling than to the other inter...

We consider electron transport through a quantum point contact between compressible Quantum Hall liquids and derive the contact’s impedance function for both diffusive and ballistic regimes of the bulk electron motion. In either regime, the tunneling current deviates from a power-law behavior I ∼ V 1/ν expected on the basis of the single-mode chiral Luttinger liquid phenomenology.

The capacitance of a nanojunction formed by a scanning tunneling microscope (STM) tip and a two-dimensional gold cluster was measured through the single electron tunneling spectroscopy of a double-barrier tunnel junction. By decreasing the STM tip-cluster separation, it was observed that the capacitance first increases and then decreases at short separation. This characteristic clearly deviates...