Yong-Hee+Lee
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3D Plasmon Antenna Capable of Focusing Light into Few Nanometers
Professors Myung-Ki Kim and Yong-Hee Lee, both of the Physics Department at KAIST, and their research teams have developed a three dimensional (3D) gap-plasmon antenna which can focus light into a space a few nanometers wide. Their research findings were published in the June 10th issue of Nano Letters.
Focusing light into a point-like space is an active research field with many applications. However, concentrating light into a smaller space than its wavelength is often hindered by diffraction. To tackle this problem, many researchers have utilized the plasmonic phenomenon of a metal where light can be confined to a greater extent by overcoming the diffraction limit.
Many researchers have focused on developing a two dimensional (2D) plasmon antenna and were able to focus a light under 5 nanometers wide. However, this 2D antenna revealed a challenge: the light disperses to the opposite end regardless of how small its beam was focused. To solve this difficulty, a 3D structure had to be employed to maximize the light's intensity.
Adopting the proximal focused-ion-beam milling technology, the KAIST research team developed a 3D four nanometer wide gap-plasmon antenna. By squeezing the photons into a 3D nano space of 4 x 10 x 10 nm3 size, the researchers were able to increase the intensity of light by 400,000 times stronger than that of the incident light. Capitalizing on the enhanced intensity of light within the antenna, they intensified the second-harmonic signal and verified that the light was focused in the nano gap by scanning cathodoluminescent images.
The researchers anticipate that this technology will improve the speed of data transfer and processing up to the level of a terahertz (one trillion times per second) and to enlarge the storage volume per unit area on hard disks by 100 times. In addition, high definition images of submolecule size can be taken with actual light, instead of with an electron microscope, while improving the semiconductor process to a smaller size of few nanometers.
Professor Kim said, “A simple yet ingenious idea has shifted the research paradigm from 2D gap-plasmon antennas to 3D antennas. This technology will see numerous applications including in the field of information technology, data storage, imaging medical science, and semiconductor processes.”
The research was sponsored by the National Research Foundation of Korea.
Figure 1: 3D Gap-Plasmon Antenna Structure and Simulation Results
Figure 2 – Constructed 3D Gap-Plasmon Antenna Structure
Figure 3 – Amplified Second Harmonic Signal Generation and Light Focused in the Nano Gap
2015.06.24 View 9775 -
Three Professors Selected as IEEE Fellows
Three Korea Advanced Institute of Science and Technology (KAIST)’s professors, Ju-Jang Lee, Yong-Hee Lee, and Hoi-Jun Yoo, were selected as a part of the 2008 Institute of Electrical and Electronics Engineers, Inc (IEEE)’s “Fellows.” A Fellow is the highest level of membership given only to those “with an extraordinary record of accomplishments” in their field of study. Although some IEEE memberships can be gained freely by all, the Fellow status is bestowed only by the IEEE Board of Directors.
Professor Ju-Jang Lee was awarded the Fellow status “for contributions to intelligent robust control and robotics.” Robust control is a system’s stable maintenance under many inputs in a dynamic environment. A part of KAIST’s Electrical Engineering Department, Professor Ju-Jang Lee has conducted successful research in these fields, and has published 538 papers. He also holds many patents in and outside of the country, and is the General Chair for two upcoming IEEE conferences in 2008 and 2009.
Professor Yong-Hee Lee of KAIST’s Physics Department was recognized for his “contributions to photonic devices based upon vertical cavity surface emitting lasers and photonic crystals.” Photonic devices are those that allow the practical use of photons, and photon crystals are structures that affect the motion of photons. Professor Yong-Hee Lee is an expert in the field of Photonics and his works have been cited over 2500 times. He is also an outstanding speaker, giving over 30 lectures in front of international audiences in the past 5 years, and receiving The Distinguished Lecturer’s Award from IEEE.
Professor Hoi-Jun Yoo was granted the prestigious Fellow status for his “contributions to low-power and high-speed VLSI design.” VLSI stands for ‘very large scale integration’ and refers to the skill for packing a huge number of semiconductors on an integrated circuit. Professor Lee’s Fellow status is noteworthy in that he studied, worked, and researched solely in Korea. He is also the youngest of the three KAIST professors to be granted membership in the class of 2008 Fellowship. IEEE also recognized Professor Yoo as the most frequent publisher during the past 8 years.
IEEE, originally concentrating on Electric Engineering, has now branched into many related fields. It is a nonprofit organization, and its aim is to be the world"s leading professional association for the advancement of technology. For its Fellow Class of 2008, 295 members were chosen; which is less that 0.1% of their total members.By KAIST Herald on December, 2007
2007.12.21 View 17396