Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Toward a quantum computer, one dot at a time

20.01.2006


Pitt researchers develop nanoscale semiconductor islands small enough to hold single electrons



Researchers at the University of Pittsburgh have developed a way to create semiconductor islands smaller than 10 nanometers in scale, known as quantum dots. The islands, made from germanium and placed on the surface of silicon with two-nanometer precision, are capable of confining single electrons.

"We believe this development moves us closer to our goal of constructing a quantum computer," said Jeremy Levy, Pitt professor of physics and astronomy and director of the Pittsburgh-based Center for Oxide-Semiconductor Materials for Quantum Computation. Levy and colleagues reported on the advance in a paper published in October 2005 in the journal Applied Physics Letters.


Quantum computers do not yet exist, but it is known that they can bypass all known encryption schemes used today on the Internet. Quantum computers also are capable of efficiently solving the most important equation in quantum physics: the Schrödinger equation, which describes the time-dependence of quantum mechanical systems. Hence, if quantum computers can be built, they likely will have as large an impact on technology as the transistor.

Electrons have a property known as "spin," which can take one of two directions--clockwise and counter-clockwise. Because of their quantum-mechanical nature, electrons can spin in both directions at once. That bizarre property allows the spin to be used as a "quantum bit" in a quantum computer. The ability to confine individual electrons, as opposed to "puddles" of electrons used in conventional computer technology, is essential for the working of a quantum computer.

The next step, said Levy, is to perform electronic and optical measurements on these materials to prove that there is indeed one electron on each quantum dot and to probe the coupling between the spins of neighbor electrons. "We can do that now because we have this control over the spacing and the size," he said.

The results achieved by Levy and colleagues are an example of "essentially nano" research, which involves manipulating properties at the smallest scales--from one to 20 nanometers.

Pitt has invested heavily in nanoscale research, beginning with the establishment of its Institute for NanoScience and Engineering (INSE), and continuing with the NanoScale Fabrication and Characterization Facility, which contains core technology such as electron-beam lithography, transmission electron microscopes, and a state-of-the-art cleanroom environment. The INSE is an integrated, multidisciplinary organization that brings coherence to the University’s research efforts and resources in the fields of nanoscale science and engineering. For more information, visit www.nano.pitt.edu.

Other researchers on the study were John T. Yates Jr., R.K. Mellon Professor of Chemistry and Physics at Pitt; former Pitt chemistry graduate student Olivier Guise; Joachim Ahner of Pittsburgh-based Seagate Technology; and Venugopalan Vaithyanathan and Darrell G. Schlom of Pennsylvania State University.

Karen Hoffmann | EurekAlert!
Further information:
http://www.pitt.edu
http://www.nano.pitt.edu

More articles from Physics and Astronomy:

nachricht Study offers new theoretical approach to describing non-equilibrium phase transitions
27.04.2017 | DOE/Argonne National Laboratory

nachricht SwRI-led team discovers lull in Mars' giant impact history
26.04.2017 | Southwest Research Institute

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Fighting drug resistant tuberculosis – InfectoGnostics meets MYCO-NET² partners in Peru

28.04.2017 | Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

 
Latest News

Wireless power can drive tiny electronic devices in the GI tract

28.04.2017 | Medical Engineering

Ice cave in Transylvania yields window into region's past

28.04.2017 | Earth Sciences

Nose2Brain – Better Therapy for Multiple Sclerosis

28.04.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>