Nanotechnology Now

Our NanoNews Digest Sponsors
Heifer International



Home > Press > World's smallest semiconductor laser heralds new era in optical science

A bright point of light from a single plasmon laser emanates from the optical setup used by UC Berkeley researchers (enlarged closeup at right). These semiconductor lasers — the world's smallest — are extremely efficient, so the small amount of scattered light is clearly visible, even in ambient room lighting. Camera saturation of the bright laser light gives the impression of a larger spot. (Courtesy of Xiang Zhang Lab/UC Berkeley)
A bright point of light from a single plasmon laser emanates from the optical setup used by UC Berkeley researchers (enlarged closeup at right). These semiconductor lasers — the world's smallest — are extremely efficient, so the small amount of scattered light is clearly visible, even in ambient room lighting. Camera saturation of the bright laser light gives the impression of a larger spot. (Courtesy of Xiang Zhang Lab/UC Berkeley)

Abstract:
Researchers at the University of California, Berkeley, have reached a new milestone in laser physics by creating the world's smallest semiconductor laser, capable of generating visible light in a space smaller than a single protein molecule.

World's smallest semiconductor laser heralds new era in optical science

Berkeley, CA | Posted on September 1st, 2009

This breakthrough, described in an advanced online publication of the journal Nature on Sunday, Aug. 30, breaks new ground in the field of optics. The UC Berkeley team not only successfully squeezed light into such a tight space, but found a novel way to keep that light energy from dissipating as it moved along, thereby achieving laser action.

"This work shatters traditional notions of laser limits, and makes a major advance toward applications in the biomedical, communications and computing fields," said Xiang Zhang, director at UC Berkeley of a National Science Foundation (NSF) Nanoscale Science and Engineering Center, and head of the research team behind this work

The achievement helps enable the development of such innovations as nanolasers that can probe, manipulate and characterize DNA molecules; optics-based telecommunications many times faster than current technology; and optical computing in which light replaces electronic circuitry with a corresponding leap in speed and processing power.

While it is traditionally accepted that an electromagnetic wave - including laser light - cannot be focused beyond the size of half its wavelength, research teams around the world have found a way to compress light down to dozens of nanometers by binding it to the electrons that oscillate collectively at the surface of metals. This interaction between light and oscillating electrons is known as surface plasmons.

Scientists have been racing to construct surface plasmon lasers that can sustain and utilize these tiny optical excitations. However, the resistance inherent in metals causes these surface plasmons to dissipate almost immediately after being generated, posing a critical challenge to achieving the buildup of the electromagnetic field necessary for lasing.

Zhang, a professor of mechanical engineering, and his research team took a novel approach to stem the loss of light energy by pairing a cadmium sulfide nanowire - 1,000 times thinner than a human hair - with a silver surface separated by an insulating gap of only 5 nanometers, the size of a single protein molecule. In this structure, the gap region stores light within an area 20 times smaller than its wavelength. Because light energy is largely stored in this tiny non-metallic gap, loss is significantly diminished.

With the loss finally under control through this unique "hybrid" design, the researchers could then work on amplifying the light.

"When you are working at such small scales, you do not have much space to play around with," said Rupert Oulton, the research associate in Zhang's lab who first theorized this approach last year and the study's co-lead author. "In our design, the nanowire acts as both a confinement mechanism and an amplifier. It's pulling double duty."

Trapping and sustaining light in radically tight quarters creates such extreme conditions that the very interaction of light and matter is strongly altered, the study authors explained. An increase in the spontaneous emission rate of light is a telltale sign of this altered interaction; in this study, the researchers measured a six-fold increase in the spontaneous emission rate of light in a gap size of 5 nanometers.

Recently, researchers from Norfolk State University reported lasing action of gold spheres in a dye-filled, glasslike shell immersed in a solution. The dye coupled to the gold spheres could generate surface plasmons when exposed to light.

The UC Berkeley researchers used semiconductor materials and fabrication technologies that are commonly employed in modern electronics manufacturing. By engineering hybrid surface plasmons in the tiny gap between semiconductors and metals, they were able to sustain the strongly confined light long enough that its oscillations stabilized into the coherent state that is a key characteristic of a laser.

"What is particularly exciting about the plasmonic lasers we demonstrated here is that they are solid state and fully compatible with semiconductor manufacturing, so they can be electrically pumped and fully integrated at chip-scale," said Volker Sorger, a Ph.D. student in Zhang's lab and study co-lead author.

"Plasmon lasers represent an exciting class of coherent light sources capable of extremely small confinement," said Zhang. "This work can bridge the worlds of electronics and optics at truly molecular length scales."

Scientists hope to eventually shrink light down to the size of an electron's wavelength, which is about a nanometer, or one-billionth of a meter, so that the two can work together on equal footing.

"The advantages of optics over electronics are multifold," added Thomas Zentgraf, a post-doctoral fellow in Zhang's lab and another co-lead author of the Nature paper. "For example, devices will be more power efficient at the same time they offer increased speed or bandwidth."

In addition to the three co-lead authors, other co-authors of the paper are Renmin Ma and Lun Dai from Peking University, and Christopher Gladden and Guy Bartal from Zhang's research group.

This work is supported by the U.S. Air Force Office of Scientific Research and the NSF.

####

About University of California, Berkeley
We teach - educating students at all levels, from undergraduate to the most advanced graduate level. Undergraduate programs are available to all eligible California high-school graduates and community college transfer students who wish to attend the University of California.

Instructional programs at the undergraduate level transmit knowledge and skills to students. At the graduate level, students experience with their instructors the processes of developing and testing new hypotheses and fresh interpretations of knowledge. Education for professional careers, grounded in understanding of relevant sciences, literature and research methods, provides individuals with the tools to continue intellectual development over a lifetime and to contribute to the needs of a changing society.

Through our academic programs, UC helps create an educated workforce that keeps the California economy competitive. And, through University Extension, with a half-million enrollments annually, UC provides continuing education for Californians to improve their job skills and enhance the quality of their lives.

For more information, please click here

Contacts:
Science/Environment/Health/ Technology
Robert Sanders

(510) 643-6998

Copyright © University of California, Berkeley

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 News Press

News and information

Flexible electronics integrated with paper-thin structure for use in space January 17th, 2025

‘Brand new physics’ for next generation spintronics: Physicists discover a unique quantum behavior that offers a new way to manipulate electron-spin and magnetization to push forward cutting-edge spintronic technologies, like computing that mimics the human brain January 17th, 2025

Quantum engineers ‘squeeze’ laser frequency combs to make more sensitive gas sensors January 17th, 2025

How a milk component could eliminate one of the biggest challenges in treating cancer and other disease, including rare diseases: Nebraska startup to use nanoparticles found in milk to target therapeutics to specific cells January 17th, 2025

Govt.-Legislation/Regulation/Funding/Policy

Department of Energy announces $71 million for research on quantum information science enabled discoveries in high energy physics: Projects combine theory and experiment to open new windows on the universe January 17th, 2025

Quantum engineers ‘squeeze’ laser frequency combs to make more sensitive gas sensors January 17th, 2025

Chainmail-like material could be the future of armor: First 2D mechanically interlocked polymer exhibits exceptional flexibility and strength January 17th, 2025

Researchers uncover strong light-matter interactions in quantum spin liquids: Groundbreaking experiment supported by Rice researcher reveals new insights into a mysterious phase of quantum matter December 13th, 2024

Nanomedicine

How a milk component could eliminate one of the biggest challenges in treating cancer and other disease, including rare diseases: Nebraska startup to use nanoparticles found in milk to target therapeutics to specific cells January 17th, 2025

Exosomes: A potential biomarker and therapeutic target in diabetic cardiomyopathy November 8th, 2024

NYU Abu Dhabi researchers develop novel covalent organic frameworks for precise cancer treatment delivery: NYU Abu Dhabi researchers develop novel covalent organic frameworks for precise cancer treatment delivery September 13th, 2024

Unveiling the power of hot carriers in plasmonic nanostructures August 16th, 2024

Optical computing/Photonic computing

Groundbreaking research unveils unified theory for optical singularities in photonic microstructures December 13th, 2024

UCF researcher discovers new technique for infrared “color” detection and imaging: The new specialized tunable detection and imaging technique for infrared photons surpasses present technology and may be a cost-effective method of capturing thermal imaging or night vision, medica December 13th, 2024

New material to make next generation of electronics faster and more efficient With the increase of new technology and artificial intelligence, the demand for efficient and powerful semiconductors continues to grow November 8th, 2024

Groundbreaking precision in single-molecule optoelectronics August 16th, 2024

Nanoelectronics

Interdisciplinary: Rice team tackles the future of semiconductors Multiferroics could be the key to ultralow-energy computing October 6th, 2023

Key element for a scalable quantum computer: Physicists from Forschungszentrum Jülich and RWTH Aachen University demonstrate electron transport on a quantum chip September 23rd, 2022

Reduced power consumption in semiconductor devices September 23rd, 2022

Atomic level deposition to extend Moore’s law and beyond July 15th, 2022

Discoveries

Autonomous AI assistant to build nanostructures: An interdisciplinary research group at TU Graz is working on constructing logic circuits through the targeted arrangement of individual molecules: Artificial intelligence should speed up the process enormously January 17th, 2025

‘Brand new physics’ for next generation spintronics: Physicists discover a unique quantum behavior that offers a new way to manipulate electron-spin and magnetization to push forward cutting-edge spintronic technologies, like computing that mimics the human brain January 17th, 2025

Quantum engineers ‘squeeze’ laser frequency combs to make more sensitive gas sensors January 17th, 2025

How a milk component could eliminate one of the biggest challenges in treating cancer and other disease, including rare diseases: Nebraska startup to use nanoparticles found in milk to target therapeutics to specific cells January 17th, 2025

Announcements

Quantum engineers ‘squeeze’ laser frequency combs to make more sensitive gas sensors January 17th, 2025

How a milk component could eliminate one of the biggest challenges in treating cancer and other disease, including rare diseases: Nebraska startup to use nanoparticles found in milk to target therapeutics to specific cells January 17th, 2025

The National Space Society Congratulates SpaceX on Starship’s 7th Test Flight: Latest Test of the Megarocket Hoped to Demonstrate a Number of New Technologies and Systems January 17th, 2025

The National Space Society Congratulates Blue Origin on the Inaugural Flight of New Glenn: The Heavy Lift Reusable Rocket Will Open New Frontiers and Provide Healthy Competition January 17th, 2025

Nanobiotechnology

How a milk component could eliminate one of the biggest challenges in treating cancer and other disease, including rare diseases: Nebraska startup to use nanoparticles found in milk to target therapeutics to specific cells January 17th, 2025

Exosomes: A potential biomarker and therapeutic target in diabetic cardiomyopathy November 8th, 2024

NYU Abu Dhabi researchers develop novel covalent organic frameworks for precise cancer treatment delivery: NYU Abu Dhabi researchers develop novel covalent organic frameworks for precise cancer treatment delivery September 13th, 2024

Nanobody inhibits metastasis of breast tumor cells to lung in mice: “In the present study we describe the development of an inhibitory nanobody directed against an extracellular epitope present in the native V-ATPase c subunit.” August 16th, 2024

Photonics/Optics/Lasers

Bringing the power of tabletop precision lasers for quantum science to the chip scale December 13th, 2024

Researchers succeed in controlling quantum states in a new energy range December 13th, 2024

Groundbreaking research unveils unified theory for optical singularities in photonic microstructures December 13th, 2024

UCF researcher discovers new technique for infrared “color” detection and imaging: The new specialized tunable detection and imaging technique for infrared photons surpasses present technology and may be a cost-effective method of capturing thermal imaging or night vision, medica December 13th, 2024

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