Exciting Discovery with a New Kind of Thin Material!

In our recent cool project with Dr. Wei-Hua Wang and Dr. Yang-hao Chan at the Institute of Atomic and Molecular Sciences in Academia Sinica, we've made a groundbreaking discovery and shared it in a science journal for 2D materials!

We worked with a super thin material called indium selenide (InSe). For the first time ever, we saw this thin layer glow brightly under certain conditions, which is a big deal because it shows us something new about how light interacts with materials.

What's really interesting is that this glow comes from something called "dark excitons." Usually, these excitons are like hidden sparks that don't give off light, making them really hard to see. But in our experiment, we found a way to make these hidden sparks shine brightly, thanks to the help of tiny vibrations called acoustic phonons and the strong interaction of exciton to these phonons. We also looked closely at how these dark excitons behave and move around in the thin layer, which helps us understand more about this fascinating material.

Our recent work, collaborating with Prof. Shun-Jen Cheng's groups in NYCU Electrophysics, "The Key Role of Non-Local Screening in the Environment-Insensitive Exciton Fine Structures of Transition-Metal Dichalcogenide Monolayers" has been published in Nanomaterials. By combining experimental measurements of binding energies under different dielectric conditions with a theoretical model of non-local screening, we provide insights into the robustness of the binding energy of dark excitons in 2D materials. This finding has significant implications for understanding the behavior of dark excitons in these materials, particularly highlighting the importance of considering non-local screening effects when studying exciton fine structures.