Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button

Home > Press > Single ‘solitons’ promising for optical technologies

Purdue researchers have used tiny microrings (top left) to generate single pulses of light called solitons, an advance that could aid efforts to develop advanced optical technologies. Two graphs show the relationship between a phenomenon called Cherenkov radiation and production of single solitons. (Purdue University photo/Chengying Bao)
Purdue researchers have used tiny microrings (top left) to generate single pulses of light called solitons, an advance that could aid efforts to develop advanced optical technologies. Two graphs show the relationship between a phenomenon called Cherenkov radiation and production of single solitons. (Purdue University photo/Chengying Bao)

Abstract:
Spatial mode-interaction induced single soliton generation in microresonators

CHENGYING BAO1,* , Y I XUAN2 DANIEL E.LEAIRD1 STEFAN WABNITZ3 MINGHAO QI1,2 AND ANDREW M.WEINER1,2

1School of Electrical & Computer Engineering, Purdue University

2Birck Nanotechnology Center, Purdue University

3Dipartimento di Ingegneria dell’Informazione, Università di Brescia, and INO-CNR, via Branze 38, 25123 Brescia, Italy *Corresponding author:

Soliton mode-locking in microresonators enables chip-scale coherent optical frequency comb generation. However, it usually leads to multi-soliton combs with a structured spectrum. Instead, the smooth spectrum of a single soliton is favored for applications. Here, we introduce, experimentally and numerically, a passive mechanism for single temporal soliton formation arising from spatial mode-interaction in microresonators. Deterministic single soliton generation is observed for microresonators with strong mode-interaction in experiments and simulations. Further simulations demonstrate that the soliton number is reduced to one in order to lower the nonlinear loss into mode-interaction-induced Cherenkov radiation (CR). Our results give important insights into soliton–CR interaction in cavities. © 2017 Optical Society of America.

Single ‘solitons’ promising for optical technologies

West Lafayette, IN | Posted on October 9th, 2017

Researchers are a step closer to harnessing single pulses of light called solitons, using tiny ring-shaped microresonators, in findings that could aid efforts to develop advanced sensors, high-speed optical communications and research tools.

Being able to harness the solitons using devices small enough to fit on an electronic chip could bring a host of applications, from miniature optical sensors that detect chemicals and biological compounds, to high-precision spectroscopy and optical communications systems that transmit greater volumes of information with better quality.

Researchers have been successful in consistently creating several solitons at a time and single solitons; however, relatively complicated “active tuning” or control is needed. Now, new findings describe a passive method that sidesteps the need of active control for single soliton generation.

“Our work has identified a new way of guiding this system into a single stable soliton,” said Andrew M. Weiner, Purdue University’s Scifres Family Distinguished Professor of Electrical and Computer Engineering.

The approach has shown how to harness a phenomenon called Cherenkov radiation, which is normally a hindrance to developing practical microresonator devices based on solitons.

“The important novelty of this work is that this Cherenkov interaction isn’t just harmful, as it is usually regarded, but actually can in some cases be harnessed to guide you to this nice clean single soliton,” Weiner said. “So, we can use Cherenkov radiation to our advantage.”

The researchers learned that having a moderately weak source of Cherenkov radiation promotes the generation of single solitons.

“We discovered that if the strength is just right it can guide you to getting a single soliton, which is really useful,” Weiner said.

Findings are detailed in research paper published on Aug. 22 in the journal Optica. The paper’s lead author was Purdue postdoctoral research associate Chengying Bao.

Solitons are short and highly stable pulses of light that form within the microring resonator and propagate stably around the ring in a circular fashion.

“Once each time around, a small portion of the soliton’s power couples out of the ring where it is available for use in measurements and applications,” Weiner said.

This happens periodically hundreds of billions of times per second because one trip around the tiny structure takes only a few picoseconds, or trillionths of a second.

Such periodic sequences of optical pulses form a “frequency comb” containing a large number of equally spaced optical frequencies. Frequency combs were demonstrated from “mode-locked” lasers more than 15 years ago, with revolutionary impacts on a wide range of precision measurement technologies and leading to the Nobel Prize in Physics in 2005. However, mode-locked lasers are relatively large and costly, which hinders deployment outside of specialized laboratories, Weiner said.

The microrings used in the Purdue study have a radius of about 100 micrometers (about the thickness of a sheet of paper) and are fabricated with a thin film of silicon nitride, a material compatible with silicon material used for electronics. Consequently, microresonators offer potential for smaller, lower cost optical frequency combs that may be compatible with widespread applications.

When there is more than one soliton within the microring, different spectral lines, or colors of light in the comb, may vary in strength.

“Some will be higher power, but some will be much weaker and not useful for applications,” Weiner said.

However, generating just a single soliton within the microring promotes a smooth comb.

“Being able to guarantee having a smooth envelope by generating single solitons, so that you don’t have some missing most of their power, would be very useful,” he said.

Producing solitons generally requires a precise control and tuning of a “continuous wave pump laser.” Generating only a single soliton requires even more complex tuning, making this feat difficult. However, the new findings suggest it is possible to produce single solitons passively, significantly simplifying the control process by taking advantage of the optical Cherenkov radiation.

“To obtain single soliton operation, the loss of energy to the Cherenkov radiation should be neither too weak nor too strong,” Weiner said. “At present the manufacturing process does not allow sufficient control over the strength of the Cherenkov radiation.”

However, future work may explore ways to more actively control the effect with more sophisticated designs based on coupling between two closely spaced microrings, which can be tuned thermally by heating them.

The single soliton combs could enable transmission of hundreds of independent communications channels in optical fibers, precise multi-frequency optical sensors that detect airborne pollutants for environmental monitoring, and ultra-precise “optical clocks” for time keeping or navigation.

“Environmental monitoring is really starting to happen with larger frequency combs based on lasers, but can we do that with chip-scale sources at lower cost for widespread use?” Weiner said. “We’re not there yet, but the potential is promising.”

The paper was authored by Bao; Yi Xuan, a research assistant professor at Purdue’s Birck Nanotechnology Center; senior research scientist Daniel E. Leaird; Stefan Wabnitz, a researcher from Università di Brescia in Italy; Minghao Qi, a Purdue professor of electrical and computer engineering; and Weiner.

The research was funded by the Defense Advanced Research Projects Agency (DARPA) (W31P40-13-1-0018); Air Force Office of Scientific Research (AFOSR) (FA9550-15-1-0211); National Science Foundation (NSF) (ECCS-1509578); and the Ministero dell’Istruzione, dell’Università e della Ricerca (MIUR) (PRIN 2015KEZNYM).

####

For more information, please click here

Contacts:
Writer:
Emil Venere
Purdue University News Service
765-494-4709


Source:
Andrew Weiner
765-494-557

Copyright © Purdue University

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 Links

Andrew Weiner:

Ultrafast Optics and Optical Fiber Communications Laboratory:

Related News Press

News and information

Sandia researchers make solid ground toward better lithium-ion battery interfaces: Reducing the traffic jam in batteries December 13th, 2017

Perking up and crimping the 'bristles' of polyelectrolyte brushes December 13th, 2017

Columbia engineers create artificial graphene in a nanofabricated semiconductor structure: Researchers are the first to observe the electronic structure of graphene in an engineered semiconductor; finding could lead to progress in advanced optoelectronics and data processing December 13th, 2017

Leti to Demo Wristband with Embedded Sensors to Diagnose Sleep Apnea: APNEAband, Which Will Be Demonstrated at CES 2018, Also Monitors Mountain Sickness, Dehydration, Dialysis Treatment Response and Epileptic Seizures December 12th, 2017

Govt.-Legislation/Regulation/Funding/Policy

Sandia researchers make solid ground toward better lithium-ion battery interfaces: Reducing the traffic jam in batteries December 13th, 2017

Perking up and crimping the 'bristles' of polyelectrolyte brushes December 13th, 2017

Columbia engineers create artificial graphene in a nanofabricated semiconductor structure: Researchers are the first to observe the electronic structure of graphene in an engineered semiconductor; finding could lead to progress in advanced optoelectronics and data processing December 13th, 2017

Wheat gets boost from purified nanotubes: Rice University toxicity study shows plant growth enhanced by -- but only by -- purified nanotubes December 6th, 2017

Sensors

Leti to Demo Wristband with Embedded Sensors to Diagnose Sleep Apnea: APNEAband, Which Will Be Demonstrated at CES 2018, Also Monitors Mountain Sickness, Dehydration, Dialysis Treatment Response and Epileptic Seizures December 12th, 2017

Leti Develops World’s First Micro-Coolers for CERN Particle Detectors: Leti Design, Fabrication and Packaging Expertise Extends to Very Large Scientific Instruments December 11th, 2017

Graphene oxide making any material suitable to create biosensors: Scientists from Tomsk Polytechnic University have developed a new tool for biomedical research focused on single-cell investigation November 27th, 2017

The stacked color sensor: True colors meet minimization November 16th, 2017

Discoveries

Sandia researchers make solid ground toward better lithium-ion battery interfaces: Reducing the traffic jam in batteries December 13th, 2017

Perking up and crimping the 'bristles' of polyelectrolyte brushes December 13th, 2017

Columbia engineers create artificial graphene in a nanofabricated semiconductor structure: Researchers are the first to observe the electronic structure of graphene in an engineered semiconductor; finding could lead to progress in advanced optoelectronics and data processing December 13th, 2017

Untangling DNA: Researchers filter the entropy out of nanopore measurements December 8th, 2017

Announcements

Sandia researchers make solid ground toward better lithium-ion battery interfaces: Reducing the traffic jam in batteries December 13th, 2017

Perking up and crimping the 'bristles' of polyelectrolyte brushes December 13th, 2017

Columbia engineers create artificial graphene in a nanofabricated semiconductor structure: Researchers are the first to observe the electronic structure of graphene in an engineered semiconductor; finding could lead to progress in advanced optoelectronics and data processing December 13th, 2017

Leti to Demo Wristband with Embedded Sensors to Diagnose Sleep Apnea: APNEAband, Which Will Be Demonstrated at CES 2018, Also Monitors Mountain Sickness, Dehydration, Dialysis Treatment Response and Epileptic Seizures December 12th, 2017

Interviews/Book Reviews/Essays/Reports/Podcasts/Journals/White papers

UCLA chemists synthesize narrow ribbons of graphene using only light and heat: Tiny structures could be next-generation solution for smaller electronic devices December 8th, 2017

Device makes power conversion more efficient: New design could dramatically cut energy waste in electric vehicles, data centers, and the power grid December 8th, 2017

Creating a new kind of metallic glass December 7th, 2017

Copper will replace toxic palladium and expensive platinum in the synthesis of medications: The effectiveness of copper nanoparticles as a catalyst has been proven December 5th, 2017

Environment

Silicon Sense first to achieve EPA approval to import detonation nanodiamonds to US: Nanodiamond additives can significantly improve the performance of metal finishing, polymer thermal and mechanical compounds, polymer coatings, CMP polishing and a range of other applications November 29th, 2017

Report highlights opportunities and risks associated with synthetic biology and bioengineering November 22nd, 2017

Dendritic fibrous nanosilica: all-in-one nanomaterial for energy, environment and health November 4th, 2017

Nano-sized gold particles have been shaped to behave as clones in biomedicine November 3rd, 2017

Grants/Sponsored Research/Awards/Scholarships/Gifts/Contests/Honors/Records

Columbia engineers create artificial graphene in a nanofabricated semiconductor structure: Researchers are the first to observe the electronic structure of graphene in an engineered semiconductor; finding could lead to progress in advanced optoelectronics and data processing December 13th, 2017

Wheat gets boost from purified nanotubes: Rice University toxicity study shows plant growth enhanced by -- but only by -- purified nanotubes December 6th, 2017

Researchers advance technique to detect ovarian cancer: Rice, MD Anderson use fluorescent carbon nanotube probes to achieve first in vivo success November 30th, 2017

Fast flowing heat in graphene heterostructures: Surprisingly fast heat flow from graphene to its surrounding November 29th, 2017

Photonics/Optics/Lasers

Leti Integrates Hybrid III-V Silicon Lasers on 200mm Wafers with Standard CMOS Process December 6th, 2017

Scientists make transparent materials absorb light December 1st, 2017

Going swimmingly: Biotemplates breakthrough paves way for cheaper nanobots: By using bacterial flagella as a template for silica, researchers have demonstrated an easier way to make propulsion systems for nanoscale swimming robots November 30th, 2017

Fast flowing heat in graphene heterostructures: Surprisingly fast heat flow from graphene to its surrounding November 29th, 2017

Research partnerships

Perking up and crimping the 'bristles' of polyelectrolyte brushes December 13th, 2017

Wheat gets boost from purified nanotubes: Rice University toxicity study shows plant growth enhanced by -- but only by -- purified nanotubes December 6th, 2017

Copper will replace toxic palladium and expensive platinum in the synthesis of medications: The effectiveness of copper nanoparticles as a catalyst has been proven December 5th, 2017

Researchers advance technique to detect ovarian cancer: Rice, MD Anderson use fluorescent carbon nanotube probes to achieve first in vivo success November 30th, 2017

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