Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Shaping a more than perfect wave

28.04.2015

Researchers of the Cluster of Excellence “Nanosystems Initiative Munich” (NIM), the Center for Nanoscience (CeNS) and the Augsburg Center for Innovative Technologies (ACIT) at Augsburg University, together with colleagues from the Institute for Integrative Nanoscience at the Leibniz Institute for Solid State and Materials Research (IFW) Dresden and the Johannes Kepler Universität (JKU) in Linz teamed up to realize the first synthesizer for tailored nanomechanical waves.

In their recent publication in "Nature Nanotechnology", NIM graduate Florian Schülein and his supervisor NIM-Professor Hubert Krenner at the chair of Experimental Physics I (Prof. Achim Wixforth) demonstrate, that nanoscale sound waves with different frequencies can be superimposed on a chip to program and synthesize a well-defined nanomechanical wave. They use these shaped waves for fast and deliberate nanomechanical control of quantum effects in a semiconductor artificial atom.


Artist impression of a nanomechanical synthesizer

© Christoph Hohmann/NIM

Back in the early 19th century, the French scientist Joseph Fourier showed that any wave can be composed of a well-defined combination of a fundamental tone and a series of overtones. This fundamental principle is used in innumerable everyday life consumer products. For example, music synthesizers like the famous ‘Hammond Organ’ generate sound using Fourier synthesis.

For MP3 encoding, the opposite procedure, Fourier analysis, is key to reach ultimate data compression. In their experiments, the team of physicists applies the fundamental principle of Fourier synthesis to generate nanomechanical sound waves of precisely defined shapes on a chip. Their approach is based on surface acoustic waves, nanoscale earthquakes, a technique Achim Wixforth and the Augsburg group are renown experts in.

“To gain full control of the shape of the nanoquake we had to develop an advanced design for the electrodes which generate the sound wave”, notes Florian Schülein. The team solved this problem by developing new electrode geometries. With these, they were able to excite not only a fundamental sine wave but also a large number of overtones at highest intensities at the same time. His supervisor, Hubert Krenner adds:

“These advanced transducers were key since all of a sudden we could really superimpose the different frequencies with unprecedented efficiency. When we combined the different frequencies with well-defined portions, and thus turned a simple sine wave into a square or triangular wave or even a short ‘kick’.”

To prove that they really generated the desired nano-wave, the researchers required fast nanoscopic ‘pressure sensors’. They used single quantum dots fabricated at IFW Dresden for this purpose. These quantum dots are nanoscopic islands which emit light in sharp spectral lines. “The emission wavelength of these artificial atoms delicately depends on the local deformation of the material,” Achim Wixforth explains.

Hence, using this opto-mechanical coupling, the nanomechanical wave was converted into an optical signal. Florian Schülein proudly adds: “Using our extremely fast stroboscope it was fantastic to see how the quantum dot spectral emission lines exactly move the way I programmed the wave!”

The Augsburg group is renowned for their pioneering work and application of surface acoustic waves. They apply these ‘nanoquakes’ to various types of nanosystems ranging from biophysical systems over microfluidics to fundamental physical effects such as the Quantum Hall Effect. All these experiments have attracted large attention worldwide and built the outstanding reputation of their research using their nanoquakes on a chip.

Based on this new breakthrough in the field of nanomechanics, researcher expect that quantum systems can be controlled in the best sense of the word quantum-mechanically using shaped and well behaved nanoquakes.

This work was supported by the Deutsche Forschungsgemeinschaft (DFG) via the Emmy Noether Programme (KR 3790/2-1), the Cluster of Excellence Nanosystems Initiative Munich (NIM), and Sonderforschungsbereich SFB 631, by BMBF via project QuaHL-Rep and by the European Union via Seventh Framework Programme project HANAS.

Reference:

Florian J. R. Schülein, Eugenio Zallo, Paola Atkinson, Oliver G. Schmidt, Rinaldo Trotta, Armando Rastelli, Achim Wixforth, and Hubert J. Krenner
Fourier synthesis of radiofrequency nanomechanical pulses with different shapes
Nature Nanotechnology – advanced online publication; doi:10.1038/nnano.2015.72 (2015)

Link: http://dx.doi.org/10.1038/nnano.2015.72

Contact:

Prof. Hubert Krenner – hubert.krenner@physik.uni-augsburg.de
Prof. Achim Wixforth – achim.wixforth@physik.uni-augsburg.de
Dr. Florian Schülein – florian.schuelein@physik.uni-augsburg.de

Lehrstuhl für Experimentalphysik I
Universität Augsburg
Universitätsstraße 1
86159 Augsburg
Telefon +49(0)821-598-3308
http://www.physik.uni-augsburg.de/lehrstuehle/exp1/

Weitere Informationen:

http://dx.doi.org/10.1038/nnano.2015.72

Klaus P. Prem | idw - Informationsdienst Wissenschaft

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 >>>