Nanotechnology Now

Our NanoNews Digest Sponsors
Heifer International

Wikipedia Affiliate Button

Home > Press > Tiny light detectors work like gecko ears

Gecko ears contain a mechanism similar to Stanford researchersí system for detecting the angle of incoming light. (Image credit: Vitaliy Halenov)
Gecko ears contain a mechanism similar to Stanford researchersí system for detecting the angle of incoming light. (Image credit: Vitaliy Halenov)

Abstract:
Geckos and many other animals have heads that are too small to triangulate the location of noises the way we do, with widely spaced ears. Instead, they have a tiny tunnel through their heads that measures the way incoming sound waves bounce around to figure out which direction they came from.

Tiny light detectors work like gecko ears

Stanford, CA | Posted on October 30th, 2018

Facing their own problem of minuscule size and triangulation, researchers from Stanford University have come up with a similar system for detecting the angle of in-coming light. Such a system could let tiny cameras detect where light is coming from, but without the bulk of a large lens.

"Making a little pixel on your photo camera that says light is coming from this or that direction is hard because, ideally, the pixels are very small - these days about 1/100th of a hair," said Mark Brongersma, professor of materials science and engineering who is senior author of a paper about this system, published Oct. 29 in Nature Nanotechnology. "So it's like having two eyes very close together and trying to cross them to see where the light is coming from."

These researchers are working on tiny detectors that could record many characteristics of light, including color, polarity and, now, angle of light. As far as they know, the system they've described in this paper is the first to demonstrate that it's possible to determine angle of light with a setup this small.

"The typical way to determine the direction of light is by using a lens. But those are big and there's no comparable mechanisms when you shrink a device so it's smaller than most bacteria," said Shanhui Fan, professor of electrical engineering, who is a co-author on the paper.

More detailed light detection could support advances in lens-less cameras, augmented reality and robotic vision, which is important for autonomous cars.

From atoms to geckos

If a sound isn't coming from directly over the top of the gecko, one eardrum essentially steals some of the sound wave energy that would otherwise tunnel through to the other. This inference helps the gecko - and about 15,000 other animal species with a similar tunnel - understand where a sound is coming from.

The researchers mimic this structure in their photodetector by having two silicon nanowires - each about 100 nanometers in diameter or about 1/1000th as wide as a hair - lined up next to each other, like the gecko's eardrums. They are positioned so closely that, when a light wave comes in at an angle, the wire closest to the light source interferes with the waves hitting its neighbor, basically casting a shadow. The first wire to detect the light would then send the strongest current. By comparing the current in both wires, the researchers can map the angle of incoming light waves.

Geckos weren't the inspiration for the initial construction of this system. Soongyu Yi, a graduate student in electrical and computer engineering at the University of Wisconsin-Madison who is lead author of the paper, came upon the likeness between their design and geckos' ears after the work had already begun. They were all surprised by the deep level of similarity. As it turns out, the same math that explains both the gecko ears and this photodetector describes an interference phenomenon between closely arranged atoms as well.

"On the theory side, it's actually very interesting to see many of the basic interference concepts that go all the way to quantum mechanics show up in a device that can be practically used," said Fan.

A long-term commitment

This project began when one of the paper's co-authors, Zongfu Yu, was a student in the Fan lab and took the initiative to combine his work there with research by Brongersma and his lab. They made progress but had to put the work on hold while Yu applied for faculty positions and, subsequently, established his lab at the University of Wisconsin-Madison, where he is now an assistant professor of electrical and computer engineering and in whose lab Soongyu Yi works.

Many years later, and after publishing the current proof-of-concept, the researchers said they look forward to building on their results. Next steps include deciding what else they might want to measure from light and putting several nanowires side-by-side to see if they can build an entire imaging system that records all the details they're interested in at once.

"We've worked on this for a long time - Zongfu has had a whole life story between the start and end of this project! It shows that we haven't compromised on quality," Brongersma said. "And it's fun to think that we might be here for another 20 years figuring out all the potential of this system."

###

Additional co-authors on this paper include Pengyu Fan, Dianmin Lin and Ken Xingze Wang of Stanford, and Nader Behdad and Ming Zhou of the University of Wisconsin-Madison. Brongersma is also a member of Stanford Bio-X, an affiliate of the Stanford Precourt Institute for Energy, and a member of the Wu Tsai Neurosciences Institute at Stanford. Fan is also director of the Edward L. Ginzton Laboratory and a senior fellow at the Stanford Precourt Institute for Energy.

This work was funded by the Office of Naval Research and the Air Force Office of Scientific Research.

####

For more information, please click here

Contacts:
Taylor Kubota

650-724-7707

Copyright © Stanford 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

RELATED JOURNAL ARTICLE:

Related News Press

News and information

Machine learning speeds modeling of experiments aimed at capturing fusion energy on Earth May 17th, 2019

Manipulating atoms one at a time with an electron beam: New method could be useful for building quantum sensors and computers May 17th, 2019

New surface treatment could improve refrigeration efficiency: A slippery surface for liquids with very low surface tension promotes droplet formation, facilitating heat transfer May 17th, 2019

Generating high-quality single photons for quantum computing: New dual-cavity design emits more single photons that can carry quantum information at room temperature May 17th, 2019

Imaging

New Argonne coating could have big implications for lithium batteries May 14th, 2019

Better microring sensors for optical applications May 10th, 2019

Scientists explore the unknown behaviour of gold nanoparticles with neutrons April 23rd, 2019

From 2D to 1D: Atomically quasi '1D' wires using a carbon nanotube template: New bulk synthesis method for nanowires of molybdenum telluride for nanoelectronics April 19th, 2019

Robotics

Dynamic hydrogel used to make 'soft robot' components and LEGO-like building blocks March 22nd, 2019

Insights into magnetic bacteria may guide research into medical nanorobots December 12th, 2018

Mode-Changing MEMS Accelerometer from STMicroelectronics Combines High Measurement Resolution and Ultra-Low Power for Industrial Applications November 7th, 2018

How to mass produce cell-sized robots: Technique from MIT could lead to tiny, self-powered devices for environmental, industrial, or medical monitoring October 24th, 2018

Govt.-Legislation/Regulation/Funding/Policy

Machine learning speeds modeling of experiments aimed at capturing fusion energy on Earth May 17th, 2019

Manipulating atoms one at a time with an electron beam: New method could be useful for building quantum sensors and computers May 17th, 2019

New way to beat the heat in electronics: Rice University lab's flexible insulator offers high strength and superior thermal conduction May 16th, 2019

New Argonne coating could have big implications for lithium batteries May 14th, 2019

Discoveries

Manipulating atoms one at a time with an electron beam: New method could be useful for building quantum sensors and computers May 17th, 2019

New surface treatment could improve refrigeration efficiency: A slippery surface for liquids with very low surface tension promotes droplet formation, facilitating heat transfer May 17th, 2019

Generating high-quality single photons for quantum computing: New dual-cavity design emits more single photons that can carry quantum information at room temperature May 17th, 2019

CEA-Leti Develops CMOS Process for High-Performance MicroLEDs That Could Overcome Display-Size Obstacles: New Concept Creates All-in-One RGB MicroLEDs, Eliminates Several Transfer Steps to Receiving Substrate & Boosts Performance May 16th, 2019

Announcements

Machine learning speeds modeling of experiments aimed at capturing fusion energy on Earth May 17th, 2019

Manipulating atoms one at a time with an electron beam: New method could be useful for building quantum sensors and computers May 17th, 2019

New surface treatment could improve refrigeration efficiency: A slippery surface for liquids with very low surface tension promotes droplet formation, facilitating heat transfer May 17th, 2019

Generating high-quality single photons for quantum computing: New dual-cavity design emits more single photons that can carry quantum information at room temperature May 17th, 2019

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

Machine learning speeds modeling of experiments aimed at capturing fusion energy on Earth May 17th, 2019

Manipulating atoms one at a time with an electron beam: New method could be useful for building quantum sensors and computers May 17th, 2019

Generating high-quality single photons for quantum computing: New dual-cavity design emits more single photons that can carry quantum information at room temperature May 17th, 2019

New way to beat the heat in electronics: Rice University lab's flexible insulator offers high strength and superior thermal conduction May 16th, 2019

Military

Manipulating atoms one at a time with an electron beam: New method could be useful for building quantum sensors and computers May 17th, 2019

New way to beat the heat in electronics: Rice University lab's flexible insulator offers high strength and superior thermal conduction May 16th, 2019

Army discovery opens path to safer batteries May 10th, 2019

Self-powered wearable tech May 8th, 2019

Automotive/Transportation

New Argonne coating could have big implications for lithium batteries May 14th, 2019

Transforming waste heat into clean energy: Researchers use supercomputers to explore new materials for thermoelectric generation May 2nd, 2019

Magnetoresistive sensors for near future innovative development March 22nd, 2019

Lightweight metal foams become bone hard and explosion proof after being nanocoated March 14th, 2019

Photonics/Optics/Lasers

Sculpting Super-Fast Light Pulses: NIST Nanopillars Shape Light Precisely for Practical Applications May 3rd, 2019

2D borophene gets a closer look: Rice, Northwestern find new ways to image, characterize unique material April 11th, 2019

New hybrid energy method could fuel the future of rockets, spacecraft for exploration: Nontraditional route shown to increase performance, burn rate April 9th, 2019

Nanoscribe is Technology Partner of the Research Project MiLiQuant: 3D microfabrication meets quantum technology - Miniaturized light sources for industrial use in the fields of quantum sensor technology and quantum imaging April 1st, 2019

Research partnerships

Manipulating atoms one at a time with an electron beam: New method could be useful for building quantum sensors and computers May 17th, 2019

New Argonne coating could have big implications for lithium batteries May 14th, 2019

Sculpting Super-Fast Light Pulses: NIST Nanopillars Shape Light Precisely for Practical Applications May 3rd, 2019

Exploring New Ways to Control Thermal Radiation April 29th, 2019

NanoNews-Digest
The latest news from around the world, FREE



  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project