Hello. My name is Donghyun Seo, and I received my Ph.D. in 2025 from the Flexible Optoelectronics Lab (led by Professor Young Min Song) at GIST. I am currently serving as an Assistant Professor in the Department of Electronic Engineering at Chosun University, dedicating myself to research and mentoring future scholars.   

Our lab specialized in optoelectronic devices. We focused primarily on three research areas: fabricating optical semiconductor devices, which have recently drawn significant attention in electrical and electronic engineering, and controlling light-matter interactions using optical structures. First, research on phototransistors that convert optical signals into electrical signals; second, research on optical modulators that control the properties of light using electrical signals; and third, research on radiative cooling, which can be applied to autonomous vehicles or buildings by controlling radiative heat.   

Because radiative cooling systems dissipate heat into outer space, experiments had to be conducted outdoors under an open sky. We often carried out outdoor experiments for several days at a time on the rooftop of the EECS building, but whenever it suddenly rained or snowed, there was a high risk of damaging the devices and equipment. What stands out most in my memory is running up to the rooftop with my lab colleagues whenever it rained to cover the equipment with umbrellas and move it to a safe place while getting soaked. Since the research was successfully completed afterward, it remains an even more rewarding experience.   

Graduate school is an environment where stress easily accumulates due to uncertainties about the future and long research hours. Rather than trying to completely eliminate all stress, it is necessary to adopt a mindset that naturally accepts a certain portion of it. Especially when misunderstandings or stress arise in research or daily life, I believe the wisest and most effective approach is not to seek distractions elsewhere, but to communicate directly with the relevant professors, colleagues, or seniors/juniors to resolve the issue at its root.   

Before entering graduate school, I worked as an intern at the Korea Institute of Ceramic Engineering and Technology (KICET), where my supervising researcher (Dr. Siyoung Bae, currently a professor at Pusan National University) was an alumnus of the GIST EECS department. Seeing him proactively plan research and achieve outstanding results as an independent researcher left a deep impression on me. Later, when I asked him for career advice, he naturally recommended GIST, which led me to decide to enroll.   

I have never once regretted completing my degree program at GIST. Having experienced other institutions—including my postdoctoral research period—I have come to realize how rare it is to find a place like GIST, where research infrastructure and advanced analysis/process facilities (such as GIST GAIA and G-NICS on the 1st floor of the EECS building) are so densely and efficiently established. It was truly an optimal environment to immerse oneself in research.   

I don’t think you need to hesitate out of worry, wondering, "Am I cut out for graduate school?" I was someone who hesitated to go to graduate school as well, but by taking the challenge and experiencing it firsthand, I was able to achieve a lot of growth. The 2 to 5 years spent in graduate school is by no means a long time in the grand scheme of one's life. I encourage you to take on the challenge with a relaxed mind, viewing it as a process to grow yourself further and expand your learning.   

As a new faculty member taking my first steps in academia, my goal is to emulate the remarkable professors I looked up to and learned from at GIST. My primary objectives for now are to solidly establish my own laboratory centered around creative research topics and to become a researcher who can conduct independent and profound studies alongside like-minded students, colleagues, and peers.   

I used to read alumni interviews and draw inspiration to dream big during my own degree course, so it is a great honor to participate as the subject of this article. As the midterm exam period of the semester has passed and we approach the end of the term, I hope everyone successfully accomplishes their final exams and remaining goals. Please take good care of your health during the seasonal change, and I will always be cheering for you.