Nanotechnology Now





Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > Scientists at PKU and UC Berkeley illustrate an atlas of carbon nanotube optical transitions

Figure 1. Scheme of determining chiral index and optical resonances of the same individual carbon nanotubes through combined electron diffraction and Rayleigh scattering techniques
Figure 1. Scheme of determining chiral index and optical resonances of the same individual carbon nanotubes through combined electron diffraction and Rayleigh scattering techniques

Abstract:
Led by Professor Wang Enge at Peking University (PKU) and Professor Wang Feng at the University of California, Berkeley, a joint research team recently reported their major progress on an atlas of carbon nanotube optical transitions, which was published in Nature Nanotechnology 7, 325 (2012).

Scientists at PKU and UC Berkeley illustrate an atlas of carbon nanotube optical transitions

Beijing, China | Posted on May 17th, 2012

Periodic table is one of the most important discoveries ever in science because it presents a systematic structure-property relation for each atom. A similar relation is equally important for nanostructures as the material properties of nanostructures depend sensitively on their structures. Single-walled carbon nanotubes (SWNTs), a model one-dimensional (1D) nanomaterial system, constitute a rich family of structures with distinctly different electrical and optical properties. The diversity of nanotube physical properties, together with their perfect structural integrity, makes SWNTs model systems to probe 1D physics and to promise materials for nanoscale electronics and photonics. However, a long-standing goal in nanotube research is how to establish the structure-property relation for hundreds of different SWNTs species with high accuracy.

The researchers illustrated the first comprehensive and accurate map between the structure and optical transitions in SWNTs through independent determination of chiral indices and optical transitions in over 200 individual nanotubes (Fig. 1). This map, effectively an "atlas" for SWNT optical transitions, has an uncertainty less than 20meV. It provides a valuable reference for nanotube spectroscopic identification, electronic and photonic applications. Once they know the optical resonances of a single-walled nanotube, they can identify its chiral index without any ambiguity, and vice versa.

In addition, this atlas opens the door for systematic understanding of fascinating 1D many-body effects in SWNTs of different types and diameters. By systematically investigating the electron-electron interaction induced optical resonance shifts in different nanotubes, they discovered surprisingly that the Fermi velocity renormalization is the same in metallic and semiconducting SWNTs, but increases monotonically with nanotube diameter towards the two-dimensional graphene limit (Fig. 2). This unusual behavior reveals an intriguing perfect cancellation of long-range electron-electron interaction effects and a diameter dependent short-range electron-electron interaction effects.

This study demonstrates the importance of a systematic approach in characterizing the property-structure relation in nanostructures. The atlas provides the prerequisite reference for the future energy-related applications. The revealed distinct behavior of long-range and short-range electron-electron interactions can be of general importance for differing low-dimensional materials.

The work was partly supported by the National Natural Science Foundation of China (NSFC) and the Ministry of Science and Technology (MOST).

Edited by: Zhang Jiang

Source: International Center for Quantum Materials

####

About Peking University
Peking University is a comprehensive and national key university. The campus, known as "Yan Yuan"(the garden of Yan), is situated at Haidian District in the western suburb of Beijing, with a total area of 2,743,532 square metres (or 274 hectares). It stands near to the Yuanmingyuan Garden and the Summer Palace.



Peking University is proud of its outstanding faculty, including 53 members of the Chinese Academy of Sciences (CAS), 7 members of the Chinese Academy of Engineering (CAE), and 14 members of the Third World Academy of Sciences (TWAS).



The university has effectively combined research on important scientific subjects with the training of personnel with a high level of specialized knowledge and professional skill as demanded by the country's socialist modernization. It strives not only for improvements in teaching and research work, but also for the promotion of interaction and mutual promotion among various disciplines.



Thus Peking University has become a center for teaching and research and a university of a new type, embracing diverse branches of learning such as basic and applied sciences, social sciences and the humanities, and sciences of medicine, management, and education. Its aim is to rank among the world's best universities in the future.

For more information, please click here

Copyright © Peking University

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

News and information

Researchers find the 'key' to quantum network solution May 25th, 2015

One step closer to a single-molecule device: Columbia Engineering researchers first to create a single-molecule diode -- the ultimate in miniaturization for electronic devices -- with potential for real-world applications May 25th, 2015

DNA Double Helix Does Double Duty in Assembling Arrays of Nanoparticles: Synthetic pieces of biological molecule form framework and glue for making nanoparticle clusters and arrays May 25th, 2015

Engineering Phase Changes in Nanoparticle Arrays: Scientists alter attractive and repulsive forces between DNA-linked particles to make dynamic, phase-shifting forms of nanomaterials May 25th, 2015

Nanotubes/Buckyballs/Fullerenes

Basel physicists develop efficient method of signal transmission from nanocomponents May 23rd, 2015

Researchers develop new way to manufacture nanofibers May 21st, 2015

Sandia researchers first to measure thermoelectric behavior by 'Tinkertoy' materials May 20th, 2015

Cotton fibres instead of carbon nanotubes May 9th, 2015

Discoveries

Researchers find the 'key' to quantum network solution May 25th, 2015

One step closer to a single-molecule device: Columbia Engineering researchers first to create a single-molecule diode -- the ultimate in miniaturization for electronic devices -- with potential for real-world applications May 25th, 2015

DNA Double Helix Does Double Duty in Assembling Arrays of Nanoparticles: Synthetic pieces of biological molecule form framework and glue for making nanoparticle clusters and arrays May 25th, 2015

Engineering Phase Changes in Nanoparticle Arrays: Scientists alter attractive and repulsive forces between DNA-linked particles to make dynamic, phase-shifting forms of nanomaterials May 25th, 2015

Announcements

Researchers find the 'key' to quantum network solution May 25th, 2015

One step closer to a single-molecule device: Columbia Engineering researchers first to create a single-molecule diode -- the ultimate in miniaturization for electronic devices -- with potential for real-world applications May 25th, 2015

DNA Double Helix Does Double Duty in Assembling Arrays of Nanoparticles: Synthetic pieces of biological molecule form framework and glue for making nanoparticle clusters and arrays May 25th, 2015

Engineering Phase Changes in Nanoparticle Arrays: Scientists alter attractive and repulsive forces between DNA-linked particles to make dynamic, phase-shifting forms of nanomaterials May 25th, 2015

Photonics/Optics/Lasers

DNA Double Helix Does Double Duty in Assembling Arrays of Nanoparticles: Synthetic pieces of biological molecule form framework and glue for making nanoparticle clusters and arrays May 25th, 2015

This Slinky lookalike 'hyperlens' helps us see tiny objects: The photonics advancement could improve early cancer detection, nanoelectronics manufacturing and scientists' ability to observe single molecules May 23rd, 2015

Samtec, Global Provider of Interconnect Systems, Joins IRT Nanoelec Silicon Photonics Program May 21st, 2015

Taking control of light emission: Researchers find a way of tuning light waves by pairing 2 exotic 2-D materials May 20th, 2015

Research partnerships

Supercomputer unlocks secrets of plant cells to pave the way for more resilient crops: IBM partners with University of Melbourne and UQ May 21st, 2015

Taking control of light emission: Researchers find a way of tuning light waves by pairing 2 exotic 2-D materials May 20th, 2015

Efficiency record for black silicon solar cells jumps to 22.1 percent: Aalto University's researchers improved their previous record by over 3 absolute percents in cooperation with Universitat Politècnica de Catalunya May 18th, 2015

Organic nanoparticles, more lethal to tumors: Carbon-based nanoparticles could be used to sensitize cancerous tumors to proton radiotherapy and induce more focused destruction of cancer cells, a new study shows May 18th, 2015

NanoNews-Digest
The latest news from around the world, FREE




  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More










ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project