* . *
  • About
  • Advertise
  • Privacy & Policy
  • Contact
Friday, August 8, 2025
Earth-News
  • Home
  • Business
  • Entertainment
    Themed Entertainment Design – Purdue Polytechnic

    Innovative Themed Entertainment Design: Creating Immersive Experiences

    Rachael Leigh Cook and Brandon Routh ‘Happy to Have Found Each Other’ Following Respective Divorces – yahoo.com

    Rachael Leigh Cook and Brandon Routh ‘Happy to Have Found Each Other’ Following Respective Divorces – yahoo.com

    ‘Billie Jean’ – Hyde Park Herald

    The Enduring Magic Behind ‘Billie Jean’ Revealed

    Hank Hill returns to a changed world in new ‘King of the Hill’ episodes – New Haven Register

    Hank Hill Navigates a Bold New World in Thrilling New ‘King of the Hill’ Episodes

    Exclusive | Fox Takes Stake in IndyCar Owner Penske Entertainment – The Wall Street Journal

    Exclusive | Fox Takes Stake in IndyCar Owner Penske Entertainment – The Wall Street Journal

    Go-to entertainment: why gaming was made for the toilet – The Guardian

    Why Gaming Is the Ultimate Way to Pass Time in the Bathroom

  • General
  • Health
  • News

    Cracking the Code: Why China’s Economic Challenges Aren’t Shaking Markets, Unlike America’s” – Bloomberg

    Trump’s Narrow Window to Spread the Truth About Harris

    Trump’s Narrow Window to Spread the Truth About Harris

    Israel-Gaza war live updates: Hamas leader Ismail Haniyeh assassinated in Iran, group says

    Israel-Gaza war live updates: Hamas leader Ismail Haniyeh assassinated in Iran, group says

    PAP Boss to Niger Delta Youths, Stay Away from the Protest

    PAP Boss to Niger Delta Youths, Stay Away from the Protest

    Court Restricts Protests In Lagos To Freedom, Peace Park

    Court Restricts Protests In Lagos To Freedom, Peace Park

    Fans React to Jazz Jennings’ Inspiring Weight Loss Journey

    Fans React to Jazz Jennings’ Inspiring Weight Loss Journey

    Trending Tags

    • Trump Inauguration
    • United Stated
    • White House
    • Market Stories
    • Election Results
  • Science
  • Sports
  • Technology
    MBU showcases student work at Occupational Therapy Technology Fair – WHSV

    Discover the Most Innovative Student Projects at the Occupational Therapy Technology Fair

    BlackSky Technology Inc. (BKSY) Reports Q2 Loss, Lags Revenue Estimates – Yahoo Finance

    BlackSky Technology Inc. Reports Q2 Loss, Misses Revenue Targets

    Improved Technology Access: A Key to Closing the Healthcare Gap for African Americans – BIOENGINEER.ORG

    LMI Expands Technology Org, Appoints New Leaders – GovCon Wire

    LMI Expands Technology Team with Dynamic New Leadership Appointments

    Midland Innovation and Technology Charter School closing down – CBS News

    Midland Innovation and Technology Charter School Closes Permanently

    Future Trends In HR Technology – Dataconomy

    Future Trends In HR Technology – Dataconomy

    Trending Tags

    • Nintendo Switch
    • CES 2017
    • Playstation 4 Pro
    • Mark Zuckerberg
No Result
View All Result
  • Home
  • Business
  • Entertainment
    Themed Entertainment Design – Purdue Polytechnic

    Innovative Themed Entertainment Design: Creating Immersive Experiences

    Rachael Leigh Cook and Brandon Routh ‘Happy to Have Found Each Other’ Following Respective Divorces – yahoo.com

    Rachael Leigh Cook and Brandon Routh ‘Happy to Have Found Each Other’ Following Respective Divorces – yahoo.com

    ‘Billie Jean’ – Hyde Park Herald

    The Enduring Magic Behind ‘Billie Jean’ Revealed

    Hank Hill returns to a changed world in new ‘King of the Hill’ episodes – New Haven Register

    Hank Hill Navigates a Bold New World in Thrilling New ‘King of the Hill’ Episodes

    Exclusive | Fox Takes Stake in IndyCar Owner Penske Entertainment – The Wall Street Journal

    Exclusive | Fox Takes Stake in IndyCar Owner Penske Entertainment – The Wall Street Journal

    Go-to entertainment: why gaming was made for the toilet – The Guardian

    Why Gaming Is the Ultimate Way to Pass Time in the Bathroom

  • General
  • Health
  • News

    Cracking the Code: Why China’s Economic Challenges Aren’t Shaking Markets, Unlike America’s” – Bloomberg

    Trump’s Narrow Window to Spread the Truth About Harris

    Trump’s Narrow Window to Spread the Truth About Harris

    Israel-Gaza war live updates: Hamas leader Ismail Haniyeh assassinated in Iran, group says

    Israel-Gaza war live updates: Hamas leader Ismail Haniyeh assassinated in Iran, group says

    PAP Boss to Niger Delta Youths, Stay Away from the Protest

    PAP Boss to Niger Delta Youths, Stay Away from the Protest

    Court Restricts Protests In Lagos To Freedom, Peace Park

    Court Restricts Protests In Lagos To Freedom, Peace Park

    Fans React to Jazz Jennings’ Inspiring Weight Loss Journey

    Fans React to Jazz Jennings’ Inspiring Weight Loss Journey

    Trending Tags

    • Trump Inauguration
    • United Stated
    • White House
    • Market Stories
    • Election Results
  • Science
  • Sports
  • Technology
    MBU showcases student work at Occupational Therapy Technology Fair – WHSV

    Discover the Most Innovative Student Projects at the Occupational Therapy Technology Fair

    BlackSky Technology Inc. (BKSY) Reports Q2 Loss, Lags Revenue Estimates – Yahoo Finance

    BlackSky Technology Inc. Reports Q2 Loss, Misses Revenue Targets

    Improved Technology Access: A Key to Closing the Healthcare Gap for African Americans – BIOENGINEER.ORG

    LMI Expands Technology Org, Appoints New Leaders – GovCon Wire

    LMI Expands Technology Team with Dynamic New Leadership Appointments

    Midland Innovation and Technology Charter School closing down – CBS News

    Midland Innovation and Technology Charter School Closes Permanently

    Future Trends In HR Technology – Dataconomy

    Future Trends In HR Technology – Dataconomy

    Trending Tags

    • Nintendo Switch
    • CES 2017
    • Playstation 4 Pro
    • Mark Zuckerberg
No Result
View All Result
Earth-News
No Result
View All Result
Home Science

Closing the green gap: A cubic III-nitride active layer with 32% internal quantum efficiency

January 23, 2024
in Science
Closing the green gap: A cubic III-nitride active layer with 32% internal quantum efficiency
Share on FacebookShare on Twitter

Mind the (green) gap

LED Light Green. Credit: The Grainger College of Engineering at University of Illinois Urbana-Champaign

Color mixing is the process of combining two or more colors: red and green make yellow, blue and red make purple, red and green and blue make white. This process of mixing colors is the basis for the future of solid-state lighting. While currently white light is achieved by phosphor down-conversion, LED color mixing actually has a higher theoretical maximum efficiency, which is needed in order to achieve the 2035 DOE energy efficiency goals.

Despite the potential efficiency of color-mixed LED sources, there exists one significant challenge: green. The “green gap” is described as the lack of suitable green LEDs. Current green LEDs are made from state-of-the-art hexagonal III-nitride but only reach one third of the efficiency goals laid out in the 2035 DOE roadmap.

In a new study, researchers at the University of Illinois Urbana-Champaign have found a potential path to fill the green gap and report a green-emitting cubic III-nitride active layer with 32% internal quantum efficiency (IQE), which is more than 6 times higher efficiency than what is reported in the literature for conventional cubic active layers.

“The ultimate goal is to triple the efficiency of today’s white light emitting diodes. And to do that, we need to fill the green gap in the spectrum, which is no easy task. You need innovation. And we show the innovation from the materials side by using cubic nitrides,” says electrical and computer engineering professor Can Bayram, who led this work alongside graduate student Jaekwon Lee.

The results of this research were recently published in Applied Physics Letters as an issue cover article.

Today, the most efficient white LEDs use blue light emitting diodes with a rare-earth phosphor coating that converts the blue light into yellow, green and/or red which enables white lighting. This process is called phosphor down-conversion. The phosphors are luminescent materials that can absorb and convert high energy photons (like blue light) into lower energy/longer wavelength light (such as green, yellow and red, respectively).

This process of phosphor down-conversion, however, has limitations. The down-conversion process is inherently inefficient because the high energy photons must lose energy (in the form of heat) to be converted into photons of other energies. Currently, white LEDs used in SSL generate seven times more heat than light output. Further, phosphors are chemically unstable and add significant raw material and packaging costs (by about 20%) to the LED device.

Despite the increase in blue LED efficiency in recent years, SSL using phosphors only has a theoretical maximum luminous efficacy of 255 lumens/watt (lm/W) whereas LED color mixing can achieve a theoretical maximum luminous efficacy of 408 lm/W.

However, many established approaches for green LEDs are plagued with “efficiency droop” at high current densities. Achieving high-efficiency green emission has been difficult with traditional hexagonal III-nitride even with increasing the indium content—a costly element required for green emission—which leads to higher defect densities and efficiency droop. This presents a fundamental challenge for the widespread adoption of SSL.

Mind the (green) gap

Closing the green gap: green emission with only 16% indium content which is much lower than hexagonal phase materials (left) and 32% IQE which is comparable to hexagonal phase materials and higher than conventional cubic active layers (right) Credit: University of Illinois Grainger College of Engineering

“We found a way to synthesize low defect density, high quality, single phase cubic gallium nitride by using an aspect ratio phase trapping technique that the Bayram group has invented,” explains Lee. In aspect ratio phase trapping, defects, as well as the undesirable hexagonal phase, are “trapped” inside the grooves so that the surface of the active layer is a perfect cubic-phase material. The cubic and hexagonal phase refers to the way atoms in the materials organize themselves.

Here, the researchers developed a cubic III-nitride system that can enable highly efficient, droop-free green LEDs with a 32% IQE and only 16% indium content. This is the highest reported IQE for cubic wells with ~30% less indium than the amount needed in a traditional hexagonal well.

Bayram says that the green gap can be closed by using cubic III-nitride, as the advantages of these materials for SSL are well documented both theoretically and experimentally. Actual efficiencies of cubic devices have been hampered by the quality and purity of the cubic phase, but the novel aspect ratio phase trapping technique used in this research enables high-quality, pure cubic III-nitride.

More information:
J. Lee et al, Green-emitting cubic GaN/In0.16Ga0.84N/GaN quantum well with 32% internal quantum efficiency at room temperature, Applied Physics Letters (2024). DOI: 10.1063/5.0179477

Citation:
Closing the green gap: A cubic III-nitride active layer with 32% internal quantum efficiency (2024, January 23)
retrieved 23 January 2024
from https://phys.org/news/2024-01-green-gap-cubic-iii-nitride.html

This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no
part may be reproduced without the written permission. The content is provided for information purposes only.

>>> Read full article>>>
Copyright for syndicated content belongs to the linked Source : Phys.org – https://phys.org/news/2024-01-green-gap-cubic-iii-nitride.html

Tags: Closingcubicscience
Previous Post

Should animals have voting rights?

Next Post

Gravity helps show strong force strength in the proton

Icing‐related injuries in polar bears (Ursus maritimus) at high latitudes – Laidre – 2024 – Ecology – ESA Journals

Frozen Peril: The Devastating Impact of Icing Injuries on Polar Bears in the High Arctic

August 8, 2025
Carnegie Science Center launching new name in September – CBS News

Carnegie Science Center Unveils Exciting New Name This September

August 8, 2025
Petersburg youth explore Coho Creek for science education – Petersburg Pilot

Petersburg Youth Dive into Science with Hands-On Exploration of Coho Creek

August 8, 2025
Is there a path to healthier aging? What the latest research shows | Bodyworks – The Oklahoman

Is there a path to healthier aging? What the latest research shows | Bodyworks – The Oklahoman

August 8, 2025
MBU showcases student work at Occupational Therapy Technology Fair – WHSV

Discover the Most Innovative Student Projects at the Occupational Therapy Technology Fair

August 8, 2025
Official | Evann Guessand completes €35m Aston Villa move – Yahoo Sports

Official | Evann Guessand completes €35m Aston Villa move – Yahoo Sports

August 8, 2025
Trailer: Netflix Animation Welcomes Viewers to the Whimsical World of Dr. Seuss! – Animation Magazine

Trailer Unveils the Whimsical World of Dr. Seuss in Netflix Animation!

August 8, 2025
Spending on AI data centers is so massive that it’s taken a bigger chunk of GDP growth than shopping—and it could crash the American economy – Fortune

Spending on AI data centers is so massive that it’s taken a bigger chunk of GDP growth than shopping—and it could crash the American economy – Fortune

August 8, 2025
SPC Health Programs Showcase: Featuring Nursing, Radiography, and Surgical Services Degrees – St. Petersburg College

Explore Exciting Career Paths in Nursing, Radiography, and Surgical Services at SPC Health Programs Showcase

August 8, 2025
Top Trump officials discussed Epstein at White House meeting Wednesday night – CNN

Top Trump officials discussed Epstein at White House meeting Wednesday night – CNN

August 8, 2025

Categories

Archives

August 2025
MTWTFSS
 123
45678910
11121314151617
18192021222324
25262728293031
« Jul    
Earth-News.info

The Earth News is an independent English-language daily published Website from all around the World News

Browse by Category

  • Business (20,132)
  • Ecology (760)
  • Economy (783)
  • Entertainment (21,659)
  • General (16,347)
  • Health (9,822)
  • Lifestyle (793)
  • News (22,149)
  • People (784)
  • Politics (792)
  • Science (15,996)
  • Sports (21,280)
  • Technology (15,763)
  • World (765)

Recent News

Icing‐related injuries in polar bears (Ursus maritimus) at high latitudes – Laidre – 2024 – Ecology – ESA Journals

Frozen Peril: The Devastating Impact of Icing Injuries on Polar Bears in the High Arctic

August 8, 2025
Carnegie Science Center launching new name in September – CBS News

Carnegie Science Center Unveils Exciting New Name This September

August 8, 2025
  • About
  • Advertise
  • Privacy & Policy
  • Contact

© 2023 earth-news.info

No Result
View All Result

© 2023 earth-news.info

No Result
View All Result

© 2023 earth-news.info

Go to mobile version