Nav: Home

Optical communication using solitons on a photonic chip

June 08, 2017

Optical solitons are special wave packages that propagate without changing their shape. They are ubiquitous in nature, and occur in Plasma Physics, water waves to biological systems. While solitons also exist in optical fiber, discovered at Bell labs in the 1980'ies, there technological use so far has been limited. While researchers studied their use for optical communication, eventually the approach was abandoned. Now, a collaboration of a research group at KIT's Institute of Photonics and Quantum Electronics (IPQ) and Institute of Microstructure Technology (IMT) with EPFL's Laboratory of Photonics and Quantum Measurements (LPQM) have shown that solitons may experience a comeback: Instead of using a train of soliton pulses in an optical fiber, they generated continuously circulating optical solitons in compact silicon nitride optical microresonators. These continuously circulating solitons lead to broadband optical frequency combs. Two such superimposed frequency combs enabled massive parallel data transmission on 179 wavelength channels at a data rate of more than 50 terabits per second - a record for frequency combs. The work is published in Nature.

Optical frequency combs, for which John Hall and Theodor W. Hänsch were awarded the Nobel Prize in Physics in 2005, consist of a multitude of neighboring spectral lines, which are aligned on a regular equidistant grid. Traditionally, frequency combs serve as high-precision optical references for measurement of frequencies. The invention of so-called Kerr frequency combs, which are characterized by large optical bandwidths and by line spacings that are optimal for communications, make frequency combs equally well suited for data transmission. Each individual spectral line can be used for transmitting a data signal.

In their experiment, the researchers from KIT and EPFL used optical silicon nitride micro-resonators on a photonic chip that can easily be integrated into compact communication systems. For the communications demonstration, two interleaved frequency combs were used to transmit data on 179 individual optical carriers, which completely cover the optical telecommunication C and L bands and allow a transmission of data rate of 55 terabits per second over a distance of 75 kilometers. "This is equivalent to more than five billion phone calls or more than two million HD TV channels. It is the highest data rate ever reached using a frequency comb source in chip format," explains Christian Koos, professor at KIT's IPQ and IMT and recipient of a Starting Independent Researcher Grant of the European Research Council (ERC) for his research on optical frequency combs.

The components have the potential to reduce the energy consumption of the light source in communication systems drastically. The basis of the researchers' work are solitons generated in low-loss optical silicon nitride micro-resonators. In these, an optical soliton state was generated for the first time by Kippenberg's lab at EPFL in 2014. "The soliton forms through nonlinear processes occurring due to the high intensity of the light field in the micro-resonator" explains Kippenberg. The microresonator is only pumped through a continuous-wave laser from which, by means of the soliton, hundreds of new equidistant laser lines are generated. The silicon nitride integrated photonic chips are grown and fabricated in the Center for MicroNanotechnology (CMi) at EPFL. Meanwhile, a startup from LPQM, LiGenTec SA, is also offering access to these photonic integrated circuits to interested academic and industrial research laboratories.

The work shows that microresonator soliton frequency comb sources can considerably increase the performance of wavelength division multiplexing (WDM) techniques in optical communications. WDM allows to transmit ultra-high data rates by using a multitude of independent data channels on a single optical waveguide. To this end, the information is encoded on laser light of different wavelengths. For coherent communications, microresonator soliton frequency comb sources can be used not only at the transmitter, but also at the receiver side of WDM systems. The comb sources dramatically increase scalability of the respective systems and enable highly parallel coherent data transmission with light. According to Christian Koos, this is an important step towards highly efficient chip-scale transceivers for future petabit networks.
This work was supported by the European Research Council (Starting Grant 'EnTeraPIC'), the European Union (project BigPipes), the Alfried Krupp von Bohlen und Halbach Foundation, the Karlsruhe School of Optics & Photonics (KSOP), and the Helmholtz International Research School for Teratronics (HIRST), the Erasmus Mundus Doctorate Program Europhotonics, the Deutsche Forschungsgemeinschaft (DFG), the European Space Agency, the US Air Force (Office of Scientific Research), the Swiss National Science Foundation (SNF), and the Defense Advanced Research Program Agency (DARPA) via the program Quantum Assisted Sensing and Readout(QuASAR).


Pablo Marin-Palomo, Juned N. Kemal, Maxim Karpov, Arne Kordts, Joerg Pfeifle, Martin H. P. Pfeiffer, Philipp Trocha, Stefan Wolf, Victor Brasch, Miles H. Anderson, Ralf Rosenberger, Kovendhan Vijayan, Wolfgang Freude, Tobias J. Kippenberg, Christian Koos. Microresonator solitons for massively parallel coherent optical communications. Nature 08 June 2017.

Ecole Polytechnique Fédérale de Lausanne

Related Optical Fiber Articles:

Scientists print nanoscale imaging probe onto tip of optical fiber
A team of researchers has developed a way to print a nanoscale imaging probe onto the tip of a glass fiber as thin as a human hair, accelerating the production of the promising new device from several per month to several per day.
Researchers develop recycling for carbon fiber composites
A WSU research team for the first time has developed a promising way to recycle the popular carbon fiber plastics that are used in everything from modern airplanes and sporting goods to the wind energy industry.
Four year agreement to supply Silicon Carbide micro-fiber
Haydale Graphene Industries plc the UK listed global nanomaterials group, is pleased to announce that its subsidiary, Advanced Composite Materials LLC, has entered into a four-year agreement to supply Silicon Carbide micro-fiber to a global industrial manufacturer of tooling and wear-resistant solutions.
New 'tougher-than-metal' fiber-reinforced hydrogels
Scientists have succeeded in creating 'fiber-reinforced soft composites,' or tough hydrogels combined with woven fiber fabric.
New discovery: Nanometric imprinting on fiber
Researchers at EPFL have come up with a way of imprinting nanometric patterns on the inside and outside of polymer fibers.
More Optical Fiber News and Optical Fiber Current Events

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Erasing The Stigma
Many of us either cope with mental illness or know someone who does. But we still have a hard time talking about it. This hour, TED speakers explore ways to push past — and even erase — the stigma. Guests include musician and comedian Jordan Raskopoulos, neuroscientist and psychiatrist Thomas Insel, psychiatrist Dixon Chibanda, anxiety and depression researcher Olivia Remes, and entrepreneur Sangu Delle.
Now Playing: Science for the People

#537 Science Journalism, Hold the Hype
Everyone's seen a piece of science getting over-exaggerated in the media. Most people would be quick to blame journalists and big media for getting in wrong. In many cases, you'd be right. But there's other sources of hype in science journalism. and one of them can be found in the humble, and little-known press release. We're talking with Chris Chambers about doing science about science journalism, and where the hype creeps in. Related links: The association between exaggeration in health related science news and academic press releases: retrospective observational study Claims of causality in health news: a randomised trial This...