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Metal additive manufacturing (AM), widely regarded as a revolution in modern manufacturing for its ability to produce lightweight and geometrically complex components, has long faced a critical barrier to widespread adoption: microscopic internal defects that are invisible to the naked eye yet significantly compromise structural integrity. Now, a research team led by Professor Hyoung Seop Kim of POSTECH has harnessed the power of artificial intelligence (AI) to overcome this challenge, marking a major leap forward in the reliability of metal 3D printing technology. Professor Hyoung Seop Kim and integrated M.S.-Ph.D. student Jeong Ah Lee, from the Graduate Institute of Ferrous & Eco Materials Technology and the Department of Materials Science and Engineering at POSTECH, collaborated with Dr. Jeong Min Park's research team at the Korea Institute of Materials Science to develop an AI-based predictive framework capable of accounting for microscopic defects in metal 3D printing processes. The findings were published in Acta Materialia, a leading international journal in materials science. Metal 3D printing works by melting and layering metal powder using a laser, a process known as laser powder bed fusion. During fabrication, small voids called pores can form inside the material, acting like air bubbles that substantially degrade the mechanical strength of finished components. In demanding applications such as aircraft structures and automotive parts, where materials are subjected to extreme conditions, even minor porosity can prove catastrophic.
Until now, assessing the effect of such defects required extensive experimentation and considerable time, posing a significant bottleneck in materials development and qualification for safety-critical industries.
▶️ Read more: https://buly.kr/DwGEv0t
▶️ DOI: /10.1016/j.actamat.2026.122101
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Professor Dong Soo Hwang’s team at POSTECH identifies the marine biological mechanism for packaging and delivering adhesive materials as nanocondensates.
How do sea squirts stay attached to rocks amid crashing waves and strong currents? Recent research has revealed that sea squirts do not simply secrete adhesive substances. Instead, they possess a unique system where they package these materials into nano-sized (nm) condensates, deliver them to the destination, and then unpack them for use on-site. Professor Dong Soo Hwang of the Division of Environmental Science and Engineering, the Division of interdisciplinary Bioscience & Bioengineering, and the Graduate School of convergence Science and Technology at POSTECH has elucidated a previously unknown internal delivery mechanism for underwater adhesive materials in sea squirts by studying their rhizoids1). This study was published in the online edition of the Proceedings of the National Academy of Sciences (PNAS).
Around the world, "ocean desertification" — the rapid disappearance of seaweed due to rising water temperatures and pollution—is accelerating. As the seafloor becomes barren, efforts are being made to artificially cultivate seaweed and transplant it back into the ocean. However, a recurring problem has been the seaweed's inability to properly attach to rocks or the seabed during its early growth stages. Although researchers investigated how marine organisms use root-like rhizoids to anchor themselves stably, the complex mechanism remained a mystery.
The research team found a crucial clue while analyzing the underwater adhesive proteins secreted from sea squirt rhizoids. They discovered that sea squirts do not secrete adhesive proteins in a simple liquid state. Instead, they combine the proteins with metal ions to create solid nanocondensates, which are tightly packaged within cells for transport. These nanocondensates, coordinated with ions such as iron (Fe), chromium (Cr), and vanadium (V), were found to act as a "protective case," shielding the proteins from the external environment as they move through the body.
▶️ Read more: https://buly.kr/DlLTtgh
▶️ DOI: /10.1073/pnas.2526665
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POSTECH and CNU demonstrate spintronic non-volatile switching with up to 66× lower energy consumption
Researchers have developed a memory technology that can store and retain data using almost no electricity by controlling spin states through temperature changes. The work, led by researchers from POSTECH and Chungnam National University, demonstrates non-volatile switching driven by temperature changes rather than electric currents. The approach could reduce energy consumption by up to 66 times compared with existing methods, and by as much as 452 times under ideal conditions. The study was published as an Inside Front Cover paper in Advanced Functional Materials. As artificial intelligence (AI) drives demand for faster and more efficient data processing, energy consumption has become a major constraint. Large data centres already consume electricity on the scale of small cities, increasing the need for low-power memory technologies. One promising candidate is spintronics, which encodes information using the spin of electrons rather than their charge. In such systems, the direction of electron spin represents binary states (0 and 1). Devices based on magnetic insulators are especially attractive because they avoid energy loss casued by current-induced heating. Most existing approaches rely on strong electric currents to switch spin directions, resulting in high energy consumption. Temperature-based methods have been proposed as a lower-power alternative, but the spin orientation typically returns to its original state when the temperature returns to its original value, making non-volatile operation difficult. The researchers overcame this limitation using thermal hysteresis—a phenomenon in which a system does not immediately return to its original state after being heated and cooled, but instead remains stable over a certain temperature range.
▶️ Read more: https://buly.kr/A47Yz20
▶️ DOI: /10.1002/adfm.202527195
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POSTECH researchers develop a bio-implant with virtually no immune response at the cellular and tissue level
Pohang, South Korea — A research team at POSTECH has developed a novel electrode that the human body does not reject. This breakthrough addresses a fundamental limitation of current wearable technology and is attracting significant attention from the academic community.
A team led by Professor Geunbae Lim of the Department of Mechanical Engineering, together with Dr. Jungho Lee and Dr. Gaeun Yun, in collaboration with Professor Sung-Min Park and Professor Chulhong Kim, has developed a ‘Dermal Bioelectrode (Dermal Electronics)’ that minimizes pain and inflammation while enabling stably biosignal measurement unaffected by external environmental factors. The study has been published as a Front Cover article in Advanced Materials, a leading international journal in the field of biomaterials.
As smartwatches measure heart rates and adhesive patches monitor blood glucose levels, wearable devices have become integral tools for everyday health management. However, the electrode technology that enables these devices still faces structural limitations. Epidermal electrodes attached to the skin surface are convenient to use but produce unstable signals due to sweat, dryness, and body movement. In contrast, microneedle electrodes inserted into the skin offer greater signal accuracy but can cause tissue irritation and inflammatory responses because of their rigid structure. As a result, users have long been forced to choose between convenience and reliability.
The team’s electrode is rigid like a needle at the moment of insertion—stiff enough to penetrate the stratum corneum—but transforms into a soft, compliant structure once it reaches the dermal layer. The concept draws on the same principle by which aluminum serves as a strong alloy in aircraft yet becomes a thin, pliable foil in the kitchen: identical materials can exhibit entirely different mechanical properties depending on their structural design.
▶️ Read more: https://buly.kr/5q9MfRN
▶️ DOI: /10.1002/adma.202509719
🌅초여름의 기운이 감돌던 2026 해맞이한마당.
우리는 함께 웃고 즐기며 캠퍼스를 가득 채웠습니다.
잠시 숨을 고르고, 그 여운을 안고, 이제 다시 여름을 맞이해봅니다.
The 2026 Sunrise Festival arrived with the first breath of early summer. We filled the campus with shared laughter and joy. As we take a moment to pause and soak in the memories, we’re ready to step into the heat of summer. ✨🌿
#POSTECH #포스텍 #해맞이한마당 #SunriseFestival #축제
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Hyper performing Laser emission technology based on OLED–liquid crystal platforms achieving tens-fold enhanced color purity over OLEDs and continuous wavelength tuning over 135 nm at 1.5 V operation
A new class of laser emission technology enabling ultra-high color purity and continuous spectral tunability at low voltage has been developed, marking a significant advance beyond conventional display light sources.
A research team led by Prof. Su Seok Choi of the Department of Electrical Engineering at POSTECH —including Hyerin Kim (M.S.), Jeongwoo Park (integrated M.S.-Ph.D. program), and Wontae Jung (Ph.D. candidate) among others—has demonstrated a next-generation laser emission platform capable of precise color control under battery-level low voltage. The study was selected as an Inside Front Cover article in the international optics journal Laser & Photonics Reviews, underscoring its scientific significance.
The clarity and purity of color are fundamentally determined by how narrowly light is confined within a specific wavelength range, typically quantified by the full width at half maximum (FWHM) of the emission spectrum. Conventional OLED-based displays exhibit relatively broad emission spectra (FWHM ~40 nm), while even advanced quantum dot (QD) emitters remain around ~30 nm. These intrinsic spectral limitations restrict color purity and pose critical challenges for emerging applications such as holographic and advanced AR/VR displays, which require laser-like ultra-narrowband (~1 nm) emission for precise optical wavefront and phase control.
In addition, existing display technologies rely on the color mixing of discrete red–green–blue (RGB) emitters, leading to structural complexity and limited capability for continuous spectral tuning. Achieving both ultra-high color purity and continuous wavelength tunability within a single device has remained a long-standing challenge.
▶️ Read more: https://buly.kr/6MtdxjO
▶️ DOI: /10.1002/lpor.202502740
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POSTECH Professor Seung-Ki Min’s Research Team Compares Future Extreme Fire Weather Under ‘Net-Zero’ vs. ‘Net-Negative’ Emission Scenarios
A research team led by Professor Seung-Ki Min of the Department of Environmental Engineering at POSTECH has found that merely achieving “carbon neutrality” by reducing emissions is not sufficient to significantly reduce extreme wildfire risk. The team argues that active “carbon reduction” - removing carbon dioxide already accumulated in the atmosphere - must be pursued in parallel. The study was recently published in Science Advances.
Large-scale wildfires are becoming more frequent and more intense worldwide. Each year, thousands of people lose their lives, ecosystems are devastated, and enormous economic losses are incurred. Wildfires are often viewed as disasters triggered by ignition sources such as lightning strikes, discarded cigarettes, or human negligence. However, the real driver lies elsewhere. Large wildfires are fundamentally driven by climate conditions shaped by temperature, humidity, and wind. As temperatures rise and the air becomes drier, forests become tinderboxes, allowing fires to burn longer and spread farther.
Using climate simulations, the POSTECH research team compared two possible futures. One scenario achieves carbon neutrality by reducing carbon dioxide emissions to “net-zero” levels. The other goes further by implementing carbon reduction measures aimed at achieving “net-negative” emissions, thereby lowering the concentration of carbon dioxide already present in the atmosphere.
The results were clear. Under the net-zero scenario, extreme fire danger remained high across many parts of the world. In some low-latitude regions of the Northern Hemisphere, the danger even increased. In contrast, under the net-negative scenario, declining atmospheric CO₂ concentrations led to lower temperatures and higher humidity, substantially reducing the conditions conductive to wildfires. These mitigating effects were particularly pronounced in regions already highly vulnerable to wildfires.
▶️ Read more: https://buly.kr/FAfVDzq
▶️ DOI: /10.1126/sciadv.adw4705
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Science publication; 20× higher deep-UV emission efficiency than conventional materials; expected to enable next-generation hygiene technologies to help curb infectious disease spread
A Korean research team has developed a new material that emits high-efficiency light in the deep-ultraviolet (DUV) range—an area long considered virtually impossible to realize with conventional semiconductor technologies.
Professor Jonghwan Kim and Professor Moon-Ho Jo of POSTECH successfully implemented a new type of quantum-well structure based on a van der Waals semiconductor material, achieving 20 times higher DUV emission efficiency than existing materials.
This achievement, supported by MSIT’s Basic Research Program (Mid-Career Researcher Program) and the Institute for Basic Science (IBS) Support Program, was published in the world-renowned journal Science on March 20.
Semiconductor light sources in the visible range have driven advances across industries, including white LED lighting, displays, and laser sources. In recent years, development has expanded toward ultraviolet (UV) LEDs, which have shorter wavelengths and higher energy than visible light. In particular, since the COVID-19 pandemic, interest has surged in DUV light sources capable of effectively inactivating bacteria and viruses.
Conventional UV LEDs primarily use gallium nitride (GaN)-based semiconductors. By replacing part of gallium (Ga) with aluminum (Al) to form aluminum gallium nitride (AlGaN), the emission wavelength can be tuned into the DUV region. However, once the wavelength reaches 200–240 nm, the light-source efficiency drops sharply to below 1%, leaving this range as a technologically challenging and largely unexplored frontier.
To overcome this limitation, the team developed a new LED nanomaterial using a van der Waals layered semiconductor. In van der Waals layered structures, atoms are strongly bonded within each atomic layer, while adjacent layers are held together by relatively weak van der Waals forces, allowing the layers to be separated and re-stacked with relative ease.
▶️ Read more: https://buly.kr/APwzUpc
▶️ DOI: science.org/doi/10.1126/science.aeb2095
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Prof. Junsuk Rho’s Research Team Publishes Two Papers in a Single Issue of Nature - A First in Korea
Professor Junsuk Rho’s research team from the Departments of Mechanical Engineering, Chemical Engineering, and Electrical Engineering at POSTECH has achieved an unprecedented milestone by publishing two papers as corresponding author in a single issue of the world’s most prestigious scientific journal, Nature.
The team drew global attention from both academia and industry by presenting two separate studies in the same issue of Nature: one on “commercial-level mass production technology for metalenses,” long considered the greatest challenge in metasurface technology, and another on “next-generation 2D and 3D switching display technology” that applies metasurfaces to practical devices.
Professor Junsuk Rho served as the corresponding author for both papers. This marks the first time that achievements led by a single research laboratory in Korea have appeared side by side in one issue of Nature.
Professor Junsuk Rho, who led the research, said, “Twenty-five years after the principles of metamaterials were first discovered, we have now fully solved the most critical challenge of mass production needed to transform science into technology. We expect these achievements to lead to groundbreaking applications in future key industries, including next-generation displays.”
▶️ Read more: https://buly.kr/31VAGKa
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Optimization Framework for High-Efficiency Thermoelectric Generators
A thermoelectric generator with a shape that no human designer would likely have imagined has now been created by a computer—and it performs more than eight times better than conventional designs. Rather than relying on intuition or repeated trial and error, the breakthrough was achieved through advanced computational optimization.
A joint research team led by Professor Jae Sung Son of the Department of Chemical Engineering at POSTECH, in collaboration with Professor Hayoung Chung of the Department of Mechanical Engineering at UNIST, has developed a general design framework that enables computers to autonomously identify the optimal structure of thermoelectric generators, which convert waste heat into electricity. Their work was recently published online in Nature Communications.
Vast amounts of energy are continuously lost as waste heat—from automobile exhaust systems and industrial processes at steel mills and semiconductor plants to even the warmth emitted from the human body. Thermoelectric power generation has long been regarded as a promising way to recover this wasted energy, as it can produce electricity from nothing more than a temperature difference, without requiring any additional fuel. It is the same principle used by NASA to power deep-space probes.
Despite steady progress in improving thermoelectric materials, device performance in real-world operating environments has often fallen short of expectations. The reason is that efficiency depends not only on the material itself but also on the device structure. A wide range of factors—including the path of heat flow, the distribution of electrical resistance, contact losses, and load conditions—must work together in a highly coordinated way for the device to perform at its full potential. Until now, most thermoelectric generator designs have been developed largely through human intuition and repeated experimental testing.
▶️ Read more: https://buly.kr/90cvGNX
▶️ DOI: /10.1038/s41467-026-69901-3
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📢Renowned Metamaterials Scholar Professor Junsuk Rho Appointed Associate Editor of Leading Applied Physics Journal ‘APL’🎉
Professor Junsuk Rho of POSTECH has been appointed an Associate Editor of Applied Physics Letters (APL), a leading journal in applied physics. His three-year term began on April 1, 2026. Published by the American Institute of Physics, APL is an internationally renowned journal in applied physics with a 65-year history. During his tenure, Professor Rho will oversee the editorial process for submissions in the fields of metamaterials, nano-optics, nanofabrication, and nanodevices. Professor Rho received his B.S. in Mechanical Engineering from Seoul National University, followed by an M.S. from the University of Illinois Urbana-Champaign and a Ph.D. from the University of California, Berkeley. Since joining POSTECH in 2014, he has led pioneering research in metamaterials—engineered materials that transcend the conventional limits of light—earning international recognition as a leading scholar in the field.
“APL is a journal with a long-standing tradition and authority in the field of applied physics,” said Professor Rho. “As Associate Editor, I will do my utmost to ensure that outstanding research in metamaterials and nano-optics is published more rapidly and fairly.”
▶️ Read more: https://buly.kr/uW1xzh
