Practical routes to isolating semiconducting and metallic single walled carbon nanotubes and key studies on their electronic and optical properties

• Applicant: Professor Dr. Mark H. Rümmeli
• Subject Area: Experimental Condensed Matter Physics
• Term: from 2009 to 2014
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 158702086

Current microelectronics is rapidly approaching physical limits and alternative approaches are needed. One of the most promising routes is molecular electronics. The development of molecular electronics is contingent on suitable molecular structures being identified, manipulated and exploited. The promise of molecular electronics has attracted the interest of the scientific community as well as the hi-tech industrial sector. Whilst the concept of molecular electronics is over three decades old, the practical realization is still in its infancy. However, modern synthesis and characterisation techniques look set to dramatically change the landscape. Among the most successful molecular systems, which have been characterized, are carbon nanotubes due to their impressive electronic properties. However, the synthesis of single walled carbon nanotubes (SWNTs), thus far, always occurs with a mixture of metallic and semiconducting tubes in the sample. For their extensive use in applications, in particular molecular electronics, one requires a significant level of control on their growth or post-synthesis manipulation. Recent advances hint that post synthesis manipulation offers very real chances for the controlled access to metallic or semiconducting SWNT. This opens up a new window of opportunity to study the fundamental nature of SWNT in greater detail than previously possible. In this project it is proposed to develop highly sophisticated separation techniques for high purity metallic or semiconducting SWNT. These separated SWNT samples will enable advanced spectroscopic studies on SWNT, most notably ground state studies and also their Tomonaga-Luttinger liquid behaviour (metallic SWNT) at low temperatures. These studies will provide new invaluable and pertinent information on the fundamental properties of these exciting molecular nanostructures.

• DFG Programme: Research Grants
• International Connection: Poland
• Participating Persons: Professor Dr. Martin Knupfer; Professorin Dr. Ewa Mijowska