• Skip to main content
  • Skip to after header navigation
  • Skip to site footer
ERN: Emerging Researchers National Conference in STEM

ERN: Emerging Researchers National Conference in STEM

  • About
    • About AAAS
    • About the NSF
    • About the Conference
    • Partners/Supporters
    • Project Team
  • Conference
  • Abstracts
    • Undergraduate Abstract Locator
    • Graduate Abstract Locator
    • Abstract Submission Process
    • Presentation Schedules
    • Abstract Submission Guidelines
    • Presentation Guidelines
  • Travel Awards
  • Resources
    • Award Winners
    • Code of Conduct-AAAS Meetings
    • Code of Conduct-ERN Conference
    • Conference Agenda
    • Conference Materials
    • Conference Program Books
    • ERN Photo Galleries
    • Events | Opportunities
    • Exhibitor Info
    • HBCU-UP/CREST PI/PD Meeting
    • In the News
    • NSF Harassment Policy
    • Plenary Session Videos
    • Professional Development
    • Science Careers Handbook
    • Additional Resources
    • Archives
  • Engage
    • Webinars
    • ERN 10-Year Anniversary Videos
    • Plenary Session Videos
  • Contact Us
  • Login

Fabrication and Characterization of Solid State White Light Emitters

Graduate #90
Discipline: Physics
Subcategory: Materials Science

Kristopher Liggins - Alabama A&M University
Co-Author(s): B. Rami Reddy and Vernessa Edwards



Now-a-days there is a great interest in developing diode pumped solid state white light emitters, because these are free from pollution, energy efficient and last longer. Our research is concentrated on developing glasses that emit white light under diode laser excitation. The investigation of the research conducted pertains to the yielding of glass that can emit white light when placed under uv-blue diode excitation. For this purpose, we have used 375 and 405 nm diode lasers. Inorganic glasses are made by the melt quenching technique. By doping the glass samples with rare-earth ions, the florescence of the glass is controlled by obtaining specific emission peaks in the red, green, and blue wavelengths. These peaks pertain to the emission of the rare-earth ions in the material when the material is exposed to the laser. To enhance the emission peaks of white light in the material, silver was added to the mixture. After concluding the preparation, the sample was then sanded and polished in order to increase the transparency and smoothness of the sample. To obtain the results, we utilized the following procedures, equipment and software in this study. The sample absorption spectrum in the visible wavelength region was recorded using Cary 3E spectrophotometer. Based on the absorption spectral wavelengths, we selected diode lasers to excite the sample. Under 405 nm excitation the sample revealed orange color emission. However, under 375 nm laser excitation, the sample revealed bright white light. Spectral analysis revealed that 405 nm laser excited Dy3+ and Sm3+ ions which emitted in the orange, red and blue wavelength regions. However, under 375 nm laser excitation the sample emitted red, yellow, green and blue wavelengths. The 375 nm laser was absorbed by Tb3+, Dy3+ and Sm3+ ions. Thus the sample emission appeared to be white in color and the sample glow is very bright. Lifetimes of the excited levels was measured to confirm that the emission is coming from different ions. The spectroscopic details will be discussed in the poster presentation. The emission spectrum was measured using a compact spectrometer. In conclusion found that white light emitting glasses are a viable option for many optical applications. By doping Tb3+, Dy3+ and Sm3+ within the glass we found that the emitting colors result in the emission of white light. This investigation will lead to more research and alterations to the initial samples created.

Funder Acknowledgement(s): NSF RISE

Faculty Advisor: Rami Bommareddi, rami.bommareddi@aamu.edu

Role: During the research I was involve in the mixing, grinding, sintering, and polishing of the glass sample. I also took the measurements for the emission and absorption of the glass before and after being polished. Additionally I was involved in background reading to find what which rare-earth ions emitted at specific wavelengths.

Sidebar

Abstract Locators

  • Undergraduate Abstract Locator
  • Graduate Abstract Locator

This material is based upon work supported by the National Science Foundation (NSF) under Grant No. DUE-1930047. Any opinions, findings, interpretations, conclusions or recommendations expressed in this material are those of its authors and do not represent the views of the AAAS Board of Directors, the Council of AAAS, AAAS’ membership or the National Science Foundation.

AAAS

1200 New York Ave, NW
Washington,DC 20005
202-326-6400
Contact Us
About Us

  • LinkedIn
  • Facebook
  • Instagram
  • Twitter
  • YouTube

The World’s Largest General Scientific Society

Useful Links

  • Membership
  • Careers at AAAS
  • Privacy Policy
  • Terms of Use

Focus Areas

  • Science Education
  • Science Diplomacy
  • Public Engagement
  • Careers in STEM

Focus Areas

  • Shaping Science Policy
  • Advocacy for Evidence
  • R&D Budget Analysis
  • Human Rights, Ethics & Law

© 2023 American Association for the Advancement of Science