On chip carbon nanotube tunneling spectroscopy

Abstract

We report an experimental study of the band structure of individual carbon nanotubes (SCNTs) based on investigation of the tunneling density of states, i.e. tunneling spectroscopy. A common approach to this task is to use a scanning tunneling microscope (STM). However, this approach has a number of drawbacks, to overcome which, we propose another method – tunneling spectroscopy of SCNTs on a chip using a tunneling contact. This method is simpler, cheaper and technologically advanced than the STM. Fabrication of a tunnel contact can be easily integrated into any technological route, therefore, a tunnel contact can be used, for example, as an additional tool in characterizing any devices based on individual CNTs. In this paper we demonstrate a simple technological procedure that results in fabrication of good-quality tunneling contacts to carbon nanotubes.

Keywords:

• Carbon nanotubes
• tunneling spectroscopy
• tunneling contact
• density of states

Additional information

Funding

This work was partially supported by the Russian Foundation for Basic Research grant No. 18-29-20116 (Design of tunneling contacts and data analysis), the Russian Foundation for Basic Research grant No. 19-32-80028 (device fabrication), and the Russian Science Foundation grant No. 14-50-00029 (transport measurements at low temperatures).