Search Menu
Photonics Media Photonics Buyers' Guide Photonics EDU Photonics Spectra BioPhotonics EuroPhotonics Vision Spectra Photonics Showcase Photonics ProdSpec Photonics Handbook
More News

Photonic Crystal Controlled by ‘Nanoquake’

Facebook Twitter LinkedIn Email Comments
MUNICH and SANTA BARBARA, Calif., Oct. 25, 2011 — Until now, the idea of an acoustically modulated photonic crystal merely existed in theory, but a new technique is proving that sound waves can control photonic crystals within a nanocavity.

Scientists working for the cluster of excellence Nanosystems Initiative Munich (NIM), the Center for Nanoscience (CeNS), the Augsburg Center for Innovative Technologies (ACIT) and the California NanoSystems Institute (CNSI) at Santa Barbara have fabricated a freestanding nanomembrane of semiconducting material. After drilling a large periodic array of tiny holes using cleanroom nanofabrication into the membrane, they trapped light of a well-defined wavelength or color inside the photonic crystal structure in a region where they skipped three holes. They placed quantum dots inside the nanocavity as light emitters.

(Image: Nanosystems Initiative Munich)

The key challenge was overlapping the wavelength of the light trapped in the nanocavity and the light emitted by the quantum dot. When the two wavelengths are in resonance, the quantum mechanical Purcell effect leads to a dramatic increase of the light extraction efficiency.

To solve this problem, the NIM-CNSI scientists used a nanoquake, or surface acoustic waves, which periodically stretch and compress the thin membrane and its precisely ordered array of holes. The nanoquakes deform the photonic crystal at radio frequency, and the wavelength of the light inside the nanocavity oscillates back and forth in less than a third of a nanosecond. This is more than 10 times faster than any other approach worldwide, the scientists say.

“The idea of an acoustically modulated photonic crystal existed in our lab for quite a long time,” said NIM graduate student Daniel Fuhrmann. “After all the hard work, it made me really proud to actually see the wavelength of the nanocavity oscillating with the shaking of the nanoquake.”

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

Based on these groundbreaking experiments, researchers expect that a highly efficient, acoustically triggered “single photon source” will be realized. Such a device is crucial for inherently secure quantum cryptography and the optical quantum computer.

For more information, visit:
Oct 2011
photonic crystal
quantum dots
Also known as QDs. Nanocrystals of semiconductor materials that fluoresce when excited by external light sources, primarily in narrow visible and near-infrared regions; they are commonly used as alternatives to organic dyes.
ACITacoustically modulated photonic crystalAmericasBiophotonicsCaliforniaCalifornia NanoSystems Institute at Santa BarbaraCeNScleanroom nanofabricationCNSIDaniel FuhrmannEuropeGermanylight sourcesnanonanocavitynanomembranenanoquakeNanosystems Initiative MunichNIMoptical quantum computeropticsphotonic crystalPurcell effectquantum cryptographyquantum dotsquantum Hall effectResearch & Technologysound wavesthe Augsburg Center for Innovative Technologiesthe Center for Nanoscience

back to top
Facebook Twitter Instagram LinkedIn YouTube RSS
©2019 Photonics Media, 100 West St., Pittsfield, MA, 01201 USA,

Photonics Media, Laurin Publishing
x We deliver – right to your inbox. Subscribe FREE to our newsletters.
We use cookies to improve user experience and analyze our website traffic as stated in our Privacy Policy. By using this website, you agree to the use of cookies unless you have disabled them.