Nanotechnology Now

Our NanoNews Digest Sponsors



Heifer International

Wikipedia Affiliate Button


android tablet pc

Home > Press > TU Vienna develops light transistor

The oscillation direction of a light wave is changed as it passes through a thin layer of a special material.
The oscillation direction of a light wave is changed as it passes through a thin layer of a special material.

Abstract:
Light can oscillate in different directions, as we can see in the 3D cinema: Each lens of the glasses only allows light of a particular oscillation direction to pass through. However, changing the polarization direction of light without a large part of it being lost is difficult. The TU Vienna has now managed this feat, using a type of light - terahertz radiation - that is of particular technological importance. An electrical field applied to an ultra-thin layer of material can turn the polarisation of the beam as required. This produces an efficient transistor for light that can be miniaturised and used to build optical computers.

TU Vienna develops light transistor

Vienna, Austria | Posted on July 9th, 2013

Rotated light - the Faraday effect

Certain materials can rotate the polarization direction of light if a magnetic field is applied to them. This is known as the Faraday effect. Normally, this effect is minutely small, however. Two years ago, Prof. Andrei Pimenov and his team at the Institute of Solid State Physics of TU Vienna, together with a research group from the University of Würzburg, managed to achieve a massive Faraday effect as they passed light through special mercury telluride platelets and applied a magnetic field.

At that time, the effect could only be controlled by an external magnetic coil, which has severe technological disadvantages. "If electro-magnets are used to control the effect, very large currents are required", explains Andrei Pimenov. Now, the turning of terahertz radiation simply by the application of an electrical potential of less than one volt has been achieved. This makes the system much simpler and faster.

It is still a magnetic field that is responsible for the fact that the polarisation is rotated, however, it is no longer the strength of the magnetic field that determines the strength of the effect, but the amount of electrons involved in the process, and this amount can be regulated simply by electrical potential. Hence only a permanent magnet and a voltage source suffice, which is technically comparatively easy to manage.

Terahertz radiation

The light used for the experiments is not visible: it is terahertz radiation with a wavelength of the order of one millimetre. "The frequency of this radiation equates to the clock frequency that the next but one generation of computers may perhaps achieve", explains Pimenov. "The components of today's computers, in which information is passed only in the form of electrical currents, cannot be fundamentally improved. To replace these currents with light would open up a range of new opportunities." It is not only in hypothetical new computers that it's important to be able to control beams of radiation precisely with the newly developed light turning mechanism: terahertz radiation is used today for many purposes, for example for imaging methods in airport security technology.

Optical transistors

If light is passed through a polarisation filter, dependent on the polarisation direction, it is either allowed to pass through or is blocked. The rotation of the beam of light (and thus the electrical potential applied) therefore determines whether a light signal is sent or blocked. "This is the very principle of a transistor", explains Pimenov: "The application of an external voltage determines whether current flows or not, and in our case, the voltage determines whether the light arrives or not." The new invention is therefore the optical equivalent of an electrical transistor.

####

About Vienna University of Technology, TU Vienna
With its eight faculties - mathematics and geo-information, physics, technical chemistry, informatics, civil engineering, architecture and regional planning, mechanical engineering and business science, electrical engineering and information technology – the Vienna University of Technology covers the classic engineering disciplines.

The TU Vienna has a great pool of specialists who are acting in a wide range of different topics in research, teaching and as partners of the economy. More than 2000 scientists do their research and teaching at highly advanced and modern institutes – in summary about 70. Although fundamental research has priority at the TU Vienna applied research is also done. Moreover services are offered as high-tech problem solving and examination expertise for industry and economy. Innovation orientated companies are highly interested in co-operating with the Vienna University of Technology because of its high-tech and high-quality research and its openness for requests of the economy.

The Vienna University of Technology puts great emphasis on co-operation between its own institutes as well as with other universities. Therefore the TU Vienna participates in several European Union (EU) and other research programmes.

The aim of the university was and still is to belong to the best. The effort to reach this aim is also expressed in its mission statement: With the aim of providing technology for people, our mission is to develop scientific excellence and wide-ranging competence in our students.

For more information, please click here

Contacts:
Bettina Neunteufl
+43 (1) 58801 41025


Prof. Andrei Pimenov
Institute of Solid State Physics
Vienna University of Technology
Wiedner Hauptstrasse 8-10, 1040 Vienna, Austria
T: +43-1-58801-137 23

Copyright © AlphaGalileo

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

Scientists reveal breakthrough in optical fiber communications December 21st, 2014

Atom-thick CCD could capture images: Rice University scientists develop two-dimensional, light-sensitive material December 20th, 2014

Oregon researchers glimpse pathway of sunlight to electricity: Collaboration with Lund University uses modified UO spectroscopy equipment to study 'maze' of connections in photoactive quantum dots December 19th, 2014

Instant-start computers possible with new breakthrough December 19th, 2014

Physics

SUNY Poly NanoCollege Faculty Member Selected as American Physical Society Fellow: SUNY Poly Associate Professor of Nanoscience Dr. Vincent LaBella Recognized for Significant Technological Innovations that Enable Interactive Learning December 17th, 2014

Fraud-proof credit card possible because of quantum physics December 16th, 2014

Nanoscale resistors for quantum devices: The electrical characteristics of new thin-film chromium oxide resistors that can be tuned by controlling the oxygen content detailed in the 'Journal of Applied Physics' December 9th, 2014

Unusual Electronic State Found in New Class of Unconventional Superconductors: Finding gives scientists a new group of materials to explore to unlock secrets of some materials' ability to carry current with no energy loss December 8th, 2014

Chip Technology

Instant-start computers possible with new breakthrough December 19th, 2014

Switching to spintronics: Berkeley Lab reports on electric field switching of ferromagnetism at room temp December 17th, 2014

Pb islands in a sea of graphene magnetise the material of the future December 16th, 2014

Stanford team combines logic, memory to build a 'high-rise' chip: Today circuit cards are laid out like single-story towns; Futuristic architecture builds layers of logic and memory into skyscraper chips that would be smaller, faster, cheaper -- and taller December 15th, 2014

Optical computing/ Photonic computing

High photosensitivity 2D-few-layered molybdenum diselenide phototransistors December 8th, 2014

Graphene layer reads optical information from nanodiamonds electronically: Possible read head for quantum computers December 1st, 2014

Penn engineers efficiently 'mix' light at the nanoscale November 17th, 2014

Nanoparticles Break the Symmetry of Light October 6th, 2014

Discoveries

Scientists reveal breakthrough in optical fiber communications December 21st, 2014

Atom-thick CCD could capture images: Rice University scientists develop two-dimensional, light-sensitive material December 20th, 2014

Oregon researchers glimpse pathway of sunlight to electricity: Collaboration with Lund University uses modified UO spectroscopy equipment to study 'maze' of connections in photoactive quantum dots December 19th, 2014

Instant-start computers possible with new breakthrough December 19th, 2014

Announcements

Scientists reveal breakthrough in optical fiber communications December 21st, 2014

Atom-thick CCD could capture images: Rice University scientists develop two-dimensional, light-sensitive material December 20th, 2014

Oregon researchers glimpse pathway of sunlight to electricity: Collaboration with Lund University uses modified UO spectroscopy equipment to study 'maze' of connections in photoactive quantum dots December 19th, 2014

Instant-start computers possible with new breakthrough December 19th, 2014

Photonics/Optics/Lasers

Scientists reveal breakthrough in optical fiber communications December 21st, 2014

Atom-thick CCD could capture images: Rice University scientists develop two-dimensional, light-sensitive material December 20th, 2014

Nanoshaping method points to future manufacturing technology December 11th, 2014

Stacking two-dimensional materials may lower cost of semiconductor devices December 11th, 2014

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







© Copyright 1999-2014 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE