Title: Unlocking the Potential of Up-Conversion Charging for Information  Storage in Phosphors

Speaker: Prof. Xiao-jun Wang

Time: 16:00-17:30, December 11, 2025

Venue: W301 Meeting Room, State Key Laboratory of Luminescent Materials and Devices (North Campus)

Abstract:

Current optical storage technologies using phosphor media struggle to achieve fast, precise data recording due to limitations of traditional charging methods. We present an up-conversion charging (UCC) approach that enables rapid, high-resolution data storage in Gd₃Ga₅O₁₂:Cr³⁺ phosphors. UCC employs two-step ionization and nonlinear charging, allowing data writing with only 0.01 s exposure per bit using a portable diode-laser engraver. This method improves recording efficiency, provides long-term data retention, and offers excellent rewritability.

Biography:

Professor Xiao-Jun Wang received his Bachelor’s degree from Jilin University, his Master’s degrees from the Chinese Academy of Sciences, and his Ph.D. in Physics from the University of Georgia, USA. He conducted postdoctoral research at Oklahoma State University and laterserved as an NIH Postdoctoral Fellow at the University of California, Irvine. Since 1995, he has been a Professor of Physics at Georgia Southern University, USA. Professor Wang’s research centers on the optical properties of solids and he has been listed among the Stanford/Elsevier Top 2% Scientists. He currently serves as Editor-in-Chief of Materials Research Bulletin and as an Editor for Light: Science & Applications. He is also a Fellow of the American Physical Society.