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[TWAS]
TWAS elected Dr. Chien-Te Chen of the NSRRC as its new Fellow member.
Distinguished scientist and NSRRC director (1997-2005) became a new member of TWAS Fellow.
2007/12/10
On November 15, 2007, Dr. Chien-Te Chen, distinguished physicist at the National Synchrotron Radiation Research Center (NSRRC) was elected as a Fellow of the Academy of Sciences for the Developing World (TWAS). The TWAS has chosen Chen for his "outstanding contribution to science and its promotion in the developing world," in the congratulation letter issued by professor Jacob Palis, President of TWAS.

TWAS currently has 880 members, including 45 scientists newly added to its existing members during its annual meeting held in Trieste, Italy this year. There are 746 Fellows and 134 associate Fellows. TWAS membership covers 90 countries; 73 in southern geographical area and 17 in the north. Among 45 new members are 4 academicians of Academia Sinica, by which total to 23 seats in Taiwan.

Chen has a long outstanding career, in particular in synchrotron science and applications. In 1985, he proposed at Bell Labs, USA, the cylindrical-element monochromator design for synchrotron radiation (SR) and constructed the world's first high-resolution, high-transmission soft X-ray beamline, dubbed "Dragon", at NSLS-U4B port in 1986-1987. During 1988, the beamline was used to measure the K-shell photoabsorption of condensed N2 to demonstrate, for the first time, that soft X-ray can reach an energy resolution of of 10-4, removing the fundamental impediment that had persisted for several decades in soft X-ray science. Since then, the Dragon design has been extended to serve the photon energy of 4-2000 eV, which cover the entire UV, VUV, and soft X-ray spectral regions. Moreover, its resolution has reached 10-5 in VUV region in recent years. Chen's invention has now been adopted by 24 synchrotron radiation (SR) facilities in Taiwan, USA, Japan, France, Germany, UK, Italy, Sweden, Switzerland, Denmark, Canada, China, Korea, India, and Brazil, making fundamental contribution to the science of synchrotron radiation worldwide.

From 1987 to1995, using the soft X-rays from the Dragon beamline and the photoelectron, photoabsorption, and magnetic circular dichroism (MCD) experimental stations designed and constructed by Chen et al. , his team has made many innovations in soft X-ray spectroscopic techniques, including high-resolution soft X-ray photoabsorption, high-resolution soft-x-ray photoemission, high accuracy fluorescence yield linearly-polarized soft X-ray photoabsorption, and soft X-ray MCD. In particular, the first soft X-ray MCD experiment carried out in 1989 has since then stirred up huge waves on soft X-ray MCD research for the past 18 years worldwide. His group has also developed the techniques for measuring element-specific three-dimensional magnetic hysteresis curves, electron orbital and spin magnetic moments, and interfacial magnetic coupling and magnetic roughness, thereby opening up new areas for research on magnetism and magnetic materials. All these experimental techniques have become invaluable tools for probing the microscopic electronic and magnetic structure of matter, and been widely adopted by the international scientific community.

The purpose of developing these soft X-ray experimental techniques is to investigate the electronic and magnetic structure of matter. Chen has investigated molecules in gas phase, surfaces/interfaces and adsorbates, semiconductors, transition metals and their compounds, high temperature superconducting cuprates (HTSC), magnetic surfaces and thin films, rare-earth ferri-magnets, alkali doped C60, colossal magnetoresistance manganese oxides (CMR), and heavy Fermion systems et al. He has more than two hundred papers published in internationally renowned journals. Among those, reports on high-accuracy experiments on HTSC, KxC60, CMR, and magnetic multi-layers are the most influential. His publications have been widely cited and made important contributions to condensed matter physics. These experiments have obtained conclusive data on the electronic or magnetic structure of these advanced materials, removed major experimental controversies, helped to test the validity of various theories, and provided a reliable microscopic foundation for new theoretical models yet to come.

After joining NSRRC of Taiwan in 1995, Chen continues to make outstanding contribution in soft X-ray science. In condensed matter physics, Chen has built a world leading soft X-ray research group and experimental facility in Taiwan. By using the advanced instrumentations developed by himself at the NSRRC, his group and international collaborators have completed many decisive experiments that provide new insights into important issues of condensed matter physics. Chen is also the inventor of the active-grating-monochromator-active-grating-spectrometer system for inelastic soft X-ray scattering, which has a theoretical data collection efficiency 100 times higher than that of the conventional designs, and an octopole superconducting magnet that can produce strong magnetic field up to 4 Tesla in arbitrary 3D direction for large angle light scattering experiments.

During his tenure as the director from 1997 to 2005, the NSRRC has seen its facility and user program significantly progressing. The facility has from 3 bending magnet beamlines in 1994 to the current 8 insertion devices (including 3 superconducting magnets). There are 32 beamlines (including 2 hard X-ray beamlines at SPring-8, Japan) and 56 experimental stations, with many designed and built in-house that have earned NSRRC international recognition. Major accelerator upgrade projects have been launched and completed on target. The superconducting RF cavity began in operation in early 2005, coined as a successful model in synchrotron light storage ring. The same year, NSRRC became the 4th synchrotron facility in the world to operate fully in top-up injection mode, demonstrating that even an early-designed, low-energy and small-circumference third generation synchrotron ring can be advanced to high-current full top-up operation with excellent beam stability. As for NSRRC user programs, scientists from both domestic and international communities conduct their advanced scientific research at the facility. There were 1300 users from 220 research groups in 2006.

Chen is an internationally renowned experimental physicist who has made innovative and monumental contributions to the science of synchrotron radiation and condensed matter physics. He has served in the science and technology advisory committees of SR facilities in China, Italy, Korea, and USA, and in the international advisory/program committees of major international scientific conferences.

TWAS is the world's leading academy for scientists from the developing world. Its membership consists of eminent scientists, more than 80 percent of whom live and work in the South. Founded and based in Trieste, TWAS also sponsors a large number of research and training programs for scientists from the developing world.
Dr. Chen with his invention, the Dragon synchrotron radiation beamline.
Invention of the Dragon Ball: a 3D-field 4 tesla cryogen-free superconducting octople magnet.