Date: Monday, January 31, 2000
Time: 17:00-18:30
Location: Rm. 400, Engineering Building 10
by Dr. Seok LEE
Photonics Research Center, Korea Institute of Science and Technology
(KIST)
Abstract
For all optical signal process, Broad-band semiconductor optical amplifiers, Wavelength Converter based on EML and EA modulator will be discussed. A possibility of a broad gain in semiconductor optical amplifier is presented by optimizing the variation of well thickness. We have obtained all optical wavelength conversion over 60 nm, using an electroabsortion modulator integrated with DFB LD. Also briefly, Technique to measure the facet reflectivity of an EA modulator using photocurrent is proposed.
Biography
Ph.D.: Dept. of Physics, Yonsei University, Seoul, Korea
MS : Dept. of Physics, Yonsei University, Seoul, Korea
BS : Dept. of Physics, Yonsei University, Seoul, Korea
Experiences
Senior Researcher, Photonics Research Center, KIST, Seoul, Korea
(7/96- present)
Visiting researcher, TADA/NAKANO Lab., Univ. of Tokyo, Tokyo, Japan
(2/95-2/96)
Post-Doctoral Researcher, Optical Electronics Lab., KIST, Seoul,
Korea (2/94-2/95)
Commissioned researcher, Optical Electronics Lab., KIST, Seoul, Korea
(9/90-1/94)
Research Interests: Tunable Laser Diode,Ý Optical functional
devices for Photonic Switches, etc.
by Dr. Young-Wan CHOI
Optical Interconnection Laboratory, Chung-Ang University
221 Heuksuk-dong, Dongjak-ku, Seoul, 156-756, Korea
Abstract
In this talk, surface normal GaAs-based optical thyristors for free space optical interconnects and waveguide-type InP-based optical thyristors for optical communications will be presented. As an attempt to improve optical sensitivity and emission efficiency, we employ quarter wavelength reflector stacks (QWRS) in GaAs-based optical thyristors. Experiments show 20% and 45% enhancement in switching voltage change and spontaneous emission efficiency, respectively. For 1.55 um InP-based optical thyristor, waveguide-type PnpN optical thyristors are proposed and fabricated for the first time. In the optical thyristor, we employ InGaAs/InP multiple quantum well (MQW) and InGaAsP bulk layers for the active n- and p-layers. The thyristors show sufficient nonlinear s-shape I-V characteristics and spontaneous emission along the waveguide. Very low switching voltages of 2.1 and 2.0 (V) for bulk and MQW thyristors, respectively, are measured.
Biography
Ph.D.: Dept. of Electrical and Computer Engineering, State Univ.
of New York at Buffalo
MS : Dept of Electrical and Computer Engineering, State Univ. of New
York at Buffalo
BS : Dept. of Electronics Engineering, Sogang University, Seoul,
Korea
3. 95. present :ÝAssociate Professor, Dept. of Electronic
Engineering, Chung-Ang University, Seoul, Korea
2. 92 2. 95 : ÝSenior Researcher, Electronics and
Telecommunications Research Institute, Daejon, Korea
8. 86 2. 92 : ÝResearch and Teaching Assistant, SUNY at
Buffalo, Buffalo, USA
Research Interests: Optical Interconnection,Ý
Microwave-Photonics,Ý Photonic Switching etc.
Refreshments will be provided.