3 years ago

Tuning 2D Light Upconversion Emission by Modulating Phonon Relaxation

Tuning 2D Light Upconversion Emission by Modulating Phonon Relaxation
Hyung Min Kim, Bum Jin Kim, Youngho Cho, Soo Yeong Lim, Yung Doug Suh, Chan Ryang Park, Sang Hwan Nam
The photonic upconversion in rare earth atoms is widely used to convert “invisible” near infrared photons to “visible” photons with continuous wave light. By using a patterned substrate, upconversion become a route for creating new information-incorporating security codes. The amount of information in the cipher increases in proportion to the number of emission colors as well as the pattern structure. Subsequently, changing the chemical composition of upconversion phosphors on 2 D substrates is required to manufacture information-rich upconversion cryptography. In this study, we exploited temperature-controlled thermal reaction on upconversion films deposited on a quartz substrate to prepare security information codes. Multiple color emission was generated from upconversion films as the result of inserting high-frequency molecular oscillators into the film structures. Fourier-transform infrared (FTIR) and time-resolved study corroborated the mechanism of spectral variation of upconversion films. Multicolor upconversion emission: 2 D upconversion films were prepared with pulsed laser deposition and their emission colors were fine-tuned by thermal surface reaction with H2O vapor. The photophysics of radiative and non-radiative relaxation in the films was investigated with FTIR and time-resolved studies.

Publisher URL: http://onlinelibrary.wiley.com/resolve/doi

DOI: 10.1002/asia.201700782

You might also like
Discover & Discuss Important Research

Keeping up-to-date with research can feel impossible, with papers being published faster than you'll ever be able to read them. That's where Researcher comes in: we're simplifying discovery and making important discussions happen. With over 19,000 sources, including peer-reviewed journals, preprints, blogs, universities, podcasts and Live events across 10 research areas, you'll never miss what's important to you. It's like social media, but better. Oh, and we should mention - it's free.

  • Download from Google Play
  • Download from App Store
  • Download from AppInChina

Researcher displays publicly available abstracts and doesn’t host any full article content. If the content is open access, we will direct clicks from the abstracts to the publisher website and display the PDF copy on our platform. Clicks to view the full text will be directed to the publisher website, where only users with subscriptions or access through their institution are able to view the full article.