Research Overview 

We pursue ultrahigh-precision measurement and control engineering enabled by advanced ultrafast lasers. Today's ultrafast lasers can generate an extremely regularly spaced train of optical pulses with ultrashort pulsewidth, ultrabroad optical spectra, and ultrahigh peak power. These multidimensional characteristics have recently created tremendous impacts in various areas, including high-field physics, frequency metrology, and biomedical imaging. Although the ultrafast laser-based science has been a huge success, the fundamental potentials enabled by such lasers have not yet been fully exploited. In particular, ultralow-noise properties of ultrafast lasers can open up new opportunities in various science and engineering areas that require ultrahigh-precision measurement and control capabilities, ranging from accelerator-based light sources through low-noise signal generators to remote sensing and industrial metrology.

Our goal is to achieve world-class performance in noise and stability of ultrafast lasers and develop new photonic technologies based on such ultrafast and ultralow-noise lasers. We have further interest in developing more robust, compact, low-noise ultrafast lasers and opening up new application areas. In the coming years, we believe that the rapid convergence of ultrafast and ultralow-noise lasers, precision measurement and control, and integrated photonic systems will unveil exciting opportunities to new directions.

Our current research has five major research areas:
(1) Ultralow-noise femtosecond lasers and frequency comb sources
(2) Timing and synchronization for ultrafast science
(3) Ultrafast and ultra-precise time-of-flight (TOF) sensing
(4) Photonic on-chip clock distribution networks
(5) Optical metrology for semiconductor device manufacturing

We gratefully acknowledge current and previous financial support for our research from
* National Research Foundation (NRF) of Korea - Young Researchers Program (2010-2013); Mid-Career Core Research Program (2012-2018); Space Technology Development Program (2013-2018); Mid-Career Research Program Type-3 [previous National Research Laboratory Program] (2018-2021)
* Institute of ICT Planning & Evaluation (IITP) of Korea - Quantum Sensor Technology Development Program (2019-2022)
* National Research Council of Science and Technology (NST) of Korea - Convergence Pilot Study Program (2020-2021)
* Samsung Electronics Future Research Center (SFRC) - Creative ICT Project (2017-2020)
* Samsung Electronics Co., Ltd. - Memory Manufacturing Operation Center Project (2016-2019)
* Korea Atomic Energy Research Institute (KAERI) - KAERI-UED Facility Project (2013-2020)
* Small and Medium Business Administration (SMBA) of Korea - Technology Innovation Program (2017-2019)
* Ministry of Trade, Industry and Energy (MOTIE) of Korea - Industrial Cooperation Region Project (2015-2018)
* KAIST - End-Run Biz-Idea Development Project (2014-2015); K-Valley RED&B Project (2015-2016)
* Korea Research Institute of Standards and Science (KRISS) - WCL Program (2013-2015)
* Pohang Accelerator Laboratory (PAL) - PAL-XFEL Project (2010-2013)
* Agency for Defense Development (ADD) of Korea - Optical Detection Sensor Project (2013)
* Ministry of Knowledge and Economy (MKE) of Korea - Technology Innovation Program (2011-2012)

[Panoramic view of the main laboratory (Room 6119)]