• HOME
  • NEWS
    • BIOENGINEERING
    • SCIENCE NEWS
  • EXPLORE
    • CAREER
      • Companies
      • Jobs
    • EVENTS
    • iGEM
      • News
      • Team
    • PHOTOS
    • VIDEO
    • WIKI
  • BLOG
  • COMMUNITY
    • FACEBOOK
    • FORUM
    • INSTAGRAM
    • TWITTER
  • CONTACT US
Wednesday, January 20, 2021
BIOENGINEER.ORG
No Result
View All Result
  • Login
  • HOME
  • NEWS
    • BIOENGINEERING
    • SCIENCE NEWS
  • EXPLORE
    • CAREER
      • Companies
      • Jobs
        • Lecturer
        • PhD Studentship
        • Postdoc
        • Research Assistant
    • EVENTS
    • iGEM
      • News
      • Team
    • PHOTOS
    • VIDEO
    • WIKI
  • BLOG
  • COMMUNITY
    • FACEBOOK
    • FORUM
    • INSTAGRAM
    • TWITTER
  • CONTACT US
  • HOME
  • NEWS
    • BIOENGINEERING
    • SCIENCE NEWS
  • EXPLORE
    • CAREER
      • Companies
      • Jobs
        • Lecturer
        • PhD Studentship
        • Postdoc
        • Research Assistant
    • EVENTS
    • iGEM
      • News
      • Team
    • PHOTOS
    • VIDEO
    • WIKI
  • BLOG
  • COMMUNITY
    • FACEBOOK
    • FORUM
    • INSTAGRAM
    • TWITTER
  • CONTACT US
No Result
View All Result
Bioengineer.org
No Result
View All Result
Home NEWS Science News

Tohoku University teaches old spectroscope new tricks

Bioengineer by Bioengineer
October 6, 2020
in Science News
0
Share on FacebookShare on TwitterShare on LinkedinShare on RedditShare on Telegram

IMAGE

Credit: Tohoku University

Tohoku University researchers have improved a method for probing semiconducting crystals with light to detect defects and impurities. The details of their ‘omnidirectional photoluminescence (ODPL) spectroscopy’ set-up were published in the journal Applied Physics Express, and could help improve the fabrication of materials for electric cars and solar cells.

“Our technique can test materials at very low temperatures and can find even small amounts of defects and impurities,” says Tohoku University materials scientist Kazunobu Kojima.

Kojima and his colleagues demonstrated their approach using gallium nitride crystals. Gallium nitride is a semiconducting crystal that has been used in energy-saving light-emitting diodes (LEDs) since the 2000s. It has interesting optic and electronic properties, making it attractive for many applications, including power-switching devices in electric vehicles. But it can develop defects and impurities during its fabrication, which can affect performance. Currently available methods for testing these crystals are expensive or too invasive.

The ODPL spectroscopy, on the other hand, is a non-invasive technique that can test the crystals, but only at room temperature. Being able to change the crystal’s temperature is important to properly test its properties.

Kojima and his colleagues found a way to set up an ODPL instrument so that the crystal can be cooled. The process involves placing a gallium nitride crystal on an aluminum plate connected to a cooling device. This is placed under an ‘integrating sphere,’ which collects light coming from many directions. External light is shone through the sphere onto the crystal, exciting it. The crystal emits light back into the sphere in order to return to its initial unexcited state. The two lights, from the external source and the crystal, are integrated within the sphere and measured by a detector. The result reveals the crystal’s ‘internal quantum efficiency,’ which is reduced if it contains defects and impurities, and can be measured even at very low temperatures.

The team’s modification – placing the crystal outside the sphere and connecting it to something that cools it – means the temperature change crucially happens only within the crystal and not within the sphere. The scientists were able to measure the internal quantum efficiency of gallium nitride samples using this technique at temperatures ranging from -261°C to about 27°C.

“We next plan to use our method for testing other materials, such as perovskites for use in highly efficient solar cells and boron nitride as an atomically thin two-dimensional material,” says Kojima.

###

Media Contact
Kazunobu Kojima
[email protected]

Original Source

https://www.tohoku.ac.jp/en/press/old_spectroscope_new_tricks.html

Related Journal Article

http://dx.doi.org/10.35848/1882-0786/abb788

Tags: Chemistry/Physics/Materials SciencesTechnology/Engineering/Computer Science
Share12Tweet8Share2ShareShareShare2

Related Posts

IMAGE

Genome editing to treat human retinal degeneration

January 19, 2021
IMAGE

Do simulations represent the real world at the atomic scale?

January 19, 2021

Protected areas vulnerable to growing emphasis on food security

January 19, 2021

Constructing termite turrets without a blueprint

January 19, 2021
Next Post
IMAGE

Astronomers turn up the heavy metal to shed light on star formation

IMAGE

Hydrogen embrittlement creates complications for clean energy storage, transportation

Leave a Reply Cancel reply

Your email address will not be published.

This site uses Akismet to reduce spam. Learn how your comment data is processed.

POPULAR NEWS

  • IMAGE

    The map of nuclear deformation takes the form of a mountain landscape

    54 shares
    Share 22 Tweet 14
  • Blood pressure drug may be key to increasing lifespan, new study shows

    44 shares
    Share 18 Tweet 11
  • New drug form may help treat osteoporosis, calcium-related disorders

    40 shares
    Share 16 Tweet 10
  • People living with HIV face premature heart disease and barriers to care

    60 shares
    Share 24 Tweet 15

About

We bring you the latest biotechnology news from best research centers and universities around the world. Check our website.

Follow us

Tags

MaterialsPublic HealthClimate ChangeChemistry/Physics/Materials SciencesBiologyInfectious/Emerging DiseasesMedicine/HealthTechnology/Engineering/Computer ScienceEcology/EnvironmentGeneticscancerCell Biology

Recent Posts

  • Genome editing to treat human retinal degeneration
  • Do simulations represent the real world at the atomic scale?
  • Protected areas vulnerable to growing emphasis on food security
  • Constructing termite turrets without a blueprint
  • Contact Us

© 2019 Bioengineer.org - Biotechnology news by Science Magazine - Scienmag.

No Result
View All Result
  • Homepages
    • Home Page 1
    • Home Page 2
  • News
  • National
  • Business
  • Health
  • Lifestyle
  • Science

© 2019 Bioengineer.org - Biotechnology news by Science Magazine - Scienmag.

Welcome Back!

Login to your account below

Forgotten Password?

Create New Account!

Fill the forms below to register

All fields are required. Log In

Retrieve your password

Please enter your username or email address to reset your password.

Log In