Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button

Home > Press > The smallest conceivable switch Targeted proton transfer within a molecule

Physicists at the Technische Universitaet Muenchen have created a nano switch based on a single porphyrin ring. If one of two protons from the inside of the ring is removed, the remaining proton can take on any one of four positions, initiated by a single tunnel electron from the tip of a scanning tunneling microscope.

Credit: Knud Seufert / Technische Universitaet Muenchen
Physicists at the Technische Universitaet Muenchen have created a nano switch based on a single porphyrin ring. If one of two protons from the inside of the ring is removed, the remaining proton can take on any one of four positions, initiated by a single tunnel electron from the tip of a scanning tunneling microscope.

Credit: Knud Seufert / Technische Universitaet Muenchen

Abstract:
For a long time miniaturization has been the magic word in electronics. Dr. Willi Auwaerter and Professor Johannes Barth, together with their team of physicists at the Technische Universitaet Muenchen (TUM), have now presented a novel molecular switch in the journal Nature Nanotechnology. Decisive for the functionality of the switch is the position of a single proton in a porphyrin ring with an inside diameter of less than half a nanometer. The physicists can set four distinct states on demand.

The smallest conceivable switch Targeted proton transfer within a molecule

Munich, Germany | Posted on December 12th, 2011

Porphyins are ring-shaped molecules that can flexibly change their structure, making them useful for a wide array of applications. Tetraphenylporphyrin is no exception: It likes to take on a saddle shape and is not limited in its functionality when it is anchored to a metal surface. The molecule holds has a pair of hydrogen atoms that can change their positions between two configurations each. At room temperature this process takes place continuously at an extremely rapid rate.

In their experiment, the scientists suppressed this spontaneous movement by cooling the sample. This allowed them to induce and observe the entire process in a single molecule using a scanning tunneling microscope. This kind of microscope is particularly well suited for the task since - in contrast to other methods - it can be used not only to determine the initial and final states, but also allows the physicists to control the hydrogen atoms directly. In a further step they removed one of the two protons from the inside of the porphyrin ring. The remaining proton could now take on any one of four positions. A tiny current that flows through the fine tip of the microscope stimulates the proton transfer, setting a specific configuration in the process.

Although the respective positions of the hydrogen atoms influence neither the basic structure of the molecule nor its bond to the metallic surface, the states are not identical. This small but significant difference, taken together with the fact that the process can be arbitrarily repeated, forms the basis of a switch whose state can be changed up to 500 times per second. A single tunneled electron initiates the proton transfer.

The molecular switch has a surface area of only one square nanometer, making it the smallest switch implemented to date. The physicists are thrilled by their demonstration and are also very happy about new insights into the mechanism behind the proton transfer resulting from their study. Knud Seufert played a key role with his experiments: "To operate a four-state switch by moving a single proton within a molecule is really fascinating and represents a true step forward in nano-scale technologies."

This research was funded by the European Research Council (ERC Advanced Grant MolArt, No. 247299), the Excellence Cluster Munich-Centre for Advanced Photonics (MAP) and the Institute for Advanced Study of the TU Muenchen.

####

For more information, please click here

Contacts:
Dr. Andreas Battenberg

49-892-891-0510

Copyright © Technische Universitaet Muenchen

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 Links

Original publication: Willi Auwaerter, Knud Seufert, Felix Bischoff, David Ecija, Saranyan Vijayaraghavan, Sushobhan Joshi, Florian Klappenberger, Niveditha Samudrala, and Johannes V. Barth

Related News Press

News and information

Harris & Harris Group Notes Announcements by Its Portfolio Companies During the Third Quarter of 2016 September 30th, 2016

INVECAS to Enable ASIC Designs for Tomorrows Intelligent Systems on GLOBALFOUNDRIES' FDX Technology: INVECAS to Collaborate with GLOBALFOUNDRIES to Provide IP and End-to-End ASIC Design Services on 22FDX and 12FDX Technologies September 30th, 2016

How to power up graphene implants without frying cells: New analysis finds way to safely conduct heat from graphene to biological tissues September 30th, 2016

Innovation in Nanotechnology is Focus of Symposium: Annual event brings international experts to Northwestern Oct. 6 September 29th, 2016

Govt.-Legislation/Regulation/Funding/Policy

How to power up graphene implants without frying cells: New analysis finds way to safely conduct heat from graphene to biological tissues September 30th, 2016

Crystalline Fault Lines Provide Pathway for Solar Cell Current: New tomographic AFM imaging technique reveals that microstructural defects, generally thought to be detrimental, actually improve conductivity in cadmium telluride solar cells September 26th, 2016

Tattoo therapy could ease chronic disease: Rice-made nanoparticles tested at Baylor College of Medicine may help control autoimmune diseases September 23rd, 2016

PHENOMEN is a FET-Open Research Project aiming to lay the foundations a new information technology September 19th, 2016

Molecular Machines

NIST illuminates transfer of nanoscale motion through microscale machine September 14th, 2016

Measuring forces in the DNA molecule: First direct measurements of base-pair bonding strength September 13th, 2016

A versatile method to pattern functionalized nanowires: A team of researchers from Hokkaido University has developed a versatile method to pattern the structure of 'nanowires,' providing a new tool for the development of novel nanodevices September 9th, 2016

Legions of nanorobots target cancerous tumors with precision: Administering anti-cancer drugs redefined August 16th, 2016

Molecular Nanotechnology

On-surface chemistry leads to novel products: On-surface chemical Reactions can lead to novel chemical compounds not yet synthesized by solution chemistry. September 13th, 2016

Measuring forces in the DNA molecule: First direct measurements of base-pair bonding strength September 13th, 2016

A versatile method to pattern functionalized nanowires: A team of researchers from Hokkaido University has developed a versatile method to pattern the structure of 'nanowires,' providing a new tool for the development of novel nanodevices September 9th, 2016

Location matters in the self-assembly of nanoclusters: Iowa State University scientists have developed a new formulation to explain an aspect of the self-assembly of nanoclusters on surfaces that has broad applications for nanotechnology September 8th, 2016

Nanoelectronics

Mexican scientist in the Netherlands seeks to achieve data transmission ... speed of light September 20th, 2016

GLOBALFOUNDRIES to Deliver Industrys Leading-Performance Offering of 7nm FinFET Technology: Company extends its leading-edge roadmap for products demanding the ultimate processing power September 15th, 2016

Semiconducting inorganic double helix: New flexible semiconductor for electronics, solar technology and photo catalysis September 15th, 2016

A versatile method to pattern functionalized nanowires: A team of researchers from Hokkaido University has developed a versatile method to pattern the structure of 'nanowires,' providing a new tool for the development of novel nanodevices September 9th, 2016

Discoveries

How to power up graphene implants without frying cells: New analysis finds way to safely conduct heat from graphene to biological tissues September 30th, 2016

Nanosensors could help determine tumors ability to remodel tissue: Measuring enzyme levels could help doctors select appropriate treatments September 29th, 2016

Fighting cancer with sticky nanoparticles September 27th, 2016

Gold nanoparticles conjugated quercetin inhibits epithelial-mesenchymal transition, angiogenesis and invasiveness via EGFR/VEGFR-2 mediated pathway in breast cancer September 27th, 2016

Announcements

Harris & Harris Group Notes Announcements by Its Portfolio Companies During the Third Quarter of 2016 September 30th, 2016

INVECAS to Enable ASIC Designs for Tomorrows Intelligent Systems on GLOBALFOUNDRIES' FDX Technology: INVECAS to Collaborate with GLOBALFOUNDRIES to Provide IP and End-to-End ASIC Design Services on 22FDX and 12FDX Technologies September 30th, 2016

How to power up graphene implants without frying cells: New analysis finds way to safely conduct heat from graphene to biological tissues September 30th, 2016

Innovation in Nanotechnology is Focus of Symposium: Annual event brings international experts to Northwestern Oct. 6 September 29th, 2016

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







Car Brands
Buy website traffic