AJF-Sponsored Activities

Recently, with the emergence of bandwidth-intensive applications such as high-resolution streaming media, 5G, cloud-based service delivery, and the Internet of Things, fiber communication network or data traffic has increased exponentially. This rapid increase in traffic in data communications highlights the increased energy demand in traditional information and communications technologies. Given the implementation cost and power consumption aspects, one of the future challenges is to continue developing core technologies such as transceiver devices and cost-effective optical components. Among the different types of materials used in the modulator device, the high-efficient electro-optic (EO) polymer has recently received intense research highlights due to the invention of achievable 100 Gbaud and beyond signaling with the extremely reduced power consumption.

EO polymers offer important advantages and promise the performance as,

• Over 70 GHz EO bandwidth, theoretically beyond 300 GHz

• 120 Gbaud NRZ electro-optic signaling with sub-one Vpp.

• Thermal stability testing fully satisfy Telcordia standards or higher temperatures.

• Promising useful PAM4 signaling beyond 200 Gbit/s

• A highly scalable platform for ultrahigh and ultradense optical communications

• Possible thermal resistance up to 110oC and high ambient temperature operation at 100oC  

Biography

Academic background

• 1994  Dr. in Engineering, Tokyo Institute of Technology, Japan

Professional career

• 1995 Researcher, National Institute for Information and Communication Technology, Japan

• 1999 Senior Researcher, National Institute for Information and Communication Technology., Japan

• 2006 Resarch Group Leader, National Institute for Information and Communication Technology., Japan

• 2007-present, Professor, Kyushu University, Japan

Research interests

Shiyoshi Yokoyama’s main interest is to develop photonic polymer and polymer optical device applications. One recent higllight is the electro-optic polymer modulator with efficient and high-speed signaling. He has aouthored and coauthored more than 140 papers in journals and conference proceeding. In 2005, he is awarded and commended for Science and Technology by the Minister of Education, Science and Technology. Currently he is coordinating the research projects funded by JSPS, SICORP JST, A-STEP JST, CREST JST, and NEDO.

Financial Sponsor

Australia-Japan Foundation

A wide untapped region exists between radio waves and light in the electromagnetic spectrum: terahertz (THz) waves. THz frequencies combine the penetration of radio waves and the large bandwidth of light, which makes them excellent candidates for next-generation information communication technology, 6G and beyond, such as ultra-broadband wireless communication, spectroscopic sensing, nondestructive imaging, and high-resolution ranging. However, THz frequencies are at the upper limit of the capabilities of conventional electronics, and the development of THz devices and systems is a challenging field of interdisciplinary research. In particular, it is difficult to generate a significant amount of power from THz sources. THz devices must, therefore, be as efficient as possible to conserve limited power. Resonant tunneling diodes, which can make the fundamental THz oscillation at room temperature, are a major candidate for both THz transmitters and receivers because of their simple and low-power consumption electronic devices. In addition, a low-loss platform for integrating THz devices is essential for various practical systems. However, the propagation loss of transmission lines based on conventional electronics is high in the THz region, mainly owing to the high ohmic loss in metals. Thus, an alternative, metal-free integrated platform based on THz silicon photonic structures is necessary to manipulate THz waves.

Biography

Masayuki Fujita received the Ph.D. degree from Yokohama National University, Yokohama, Japan, where he focused on ultrasmall and ultralow-threshold microdisk lasers, in 2002. Subsequently, he joined the Department of Electronic Science and Engineering, Kyoto University, Kyoto, Japan, and initiated research on photonic crystals, including spontaneous emission control in photonic crystals and high-efficiency light extraction in light-emitting diodes and silicon light emitters. Next, he moved to Osaka University, Toyonaka, Japan, in 2011 and was appointed the Research Director of the strategic basic research program CREST, “Development of terahertz integrated technology platform through fusion of resonant tunneling diodes and photonic crystals” (2015-2021) and “Development of integrated devices and systems to control time domain and space distribution of terahertz waves,” (2021-) of the Japan Science and Technology Agency. He is currently an Associate Professor with the Graduate School of Engineering Science, Osaka University. His research interests include terahertz materials, devices, systems, and photonic nanostructures, microstructures, and their applications. He is a Member of the Japan Society of Applied Physics, the Laser Society of Japan, the Institute of Electronics, Information and Communication Engineers (IEICE), Japan, the Japanese Photochemistry Association, and Optica, formerly OSA. From 1999 to 2002 and from 2003 to 2006, he was a Research Fellow of the Japan Society for the Promotion of Science. He is currently a Vice-chair of IEICE Technical Committee on Microwave Photonics and Terahertz Photonic-Electronics Technologies, Japan.

Financial Sponsor

Australia-Japan Foundation