LI Detian is an academician of the Chinese Academy of Engineering and the International Academy of Astronautics, the winner of National Natural Science Foundation Outstanding Youth Science Fund, and selected by the national Millions of Talents Program, the Leading Talent of Technological Innovation of Ten-Thousands Talents Program. He currently serves as the director of the Science and Technology Commission of Lanzhou Institute of Physics (LIP), and concurrently serves as the executive deputy director of the key laboratory of vacuum technology and physics, the vice chairman of the Chinese Vacuum Society, the Chinese Society for Measurement, the Special Committee for Electrical Propulsion of the Chinese Society of Astronautics, and the chief editor of Vacuum and Cryogenics.
Li is the leading expert in the field of vacuum measurement and metrology, and has long been engaged in the research of vacuum measurement technology and multiple parameters tests in vacuum environment, successfully leading the team to solve the measurement problems of vacuum neutral gas, vacuum plasma and complex vacuum effects, making systematic contributions in metrology technology, metrology standard, apparatus and engineering applications, along with ground tests, earth orbit satellites and deep space explorations. He has published more than 200 academic papers and 8 books. He has won the second prize of the National Technological Invention Award, the second prize of the National Science and Technology Progress Award etc. He has also won the Ho Leung Ho Lee Science and Technology Innovation Award, the National Innovation Competition Award, the China Vacuum Science and Technology Achievement Award, the Aerospace Innovation Award, and the Aerospace Contribution Award.
Research and Applications of Carbon Nanotube Sources in Vacuum Measurement Technology in LIP
Carbon nanotube (CNT) film has unique field emission characteristics and a series of advantages as an electron or ion source, such as operating at room temperature, stable physical and chemical properties, as well as fast response time, which can be potentially applied to various electronic vacuum devices.
From aspects of preparation, device design and instrument applications of CNT sources, the talk will present the research work of Lanzhou Institute of Physics in recent years on vacuum instruments or key components, such as ionization vacuum gauge, metrological ultrahigh vacuum gauge, mass spectrometer ion source, standard low-energy ion source, and expound in detail the series of key technologies and characteristics of the new CNT source coupling with the above kinds of electronic vacuum devices.
The National Science Fund for Distinguished Young Scholars, Leading talents in Scientific and Technological Innovation of the National ten thousand Talents Plan.
Awardee of 2019 China State Science Award(1st), 2020 Ho Leung Ho Lee Award, 2020 Special award of China Youth Science and Technology Award, 2020 Xplore Prize, 2017 IEEE NPSS Early Achievement Award, 2018 Tan Kah Kee Young Scientist Award, AAPPS-DPP Young Scientist Award.
He is the founding Chair of IEEE NPSS Xi’an Chapter (1st NPSS Chapter established in China), Senior Editor of IEEE Trans. Plasma Science, Associate Editor of IEEE Trans. Micro. Theor. Tech., IEEE Senior Member, the General Chair of 2018 Asia-Pacific Conference on Plasma and Terahertz Science, and The technical Programm Chair of 2020 47th ICOPS.
He is the Chief Scientist of China National Scientific Innovation District, Academic Board of China National Key Laboratory of Science and Technology on Space Microwave, Chair of China Terahertz Biophysics Committee, Asociate Chair of China Terahertz Committee, Editorial Board of Vacuum Electronics (Journal of Chinese).
Prof. Chang was born in 1983, received Bachelor in 2006 and Ph.D. in 2010 both from Tsinghua University, and Postdoctorial in 2011-2013 from Stanford University. He is Associate Director of Advanced Interdisciplinary Technology Research Center of National Innovation Institute of Defense Technology.
He studied the mechanisms of intense nanosecond microwave-driven window breakdown and discovered effective methods of multipactor suppression on windows and in dielectric-loaded accelerators, proposed the novel electromagnetic undulators for free electron lasers, and proposed the relay communication of Terahertz/Infared in nerve axcon. As the 1st and correspondence author, he has published more than 60 peer-reviewed papers, including Nature Comm., PNAS, 2 PRL, JACS, 7 APL, AFM, JPCL, and authorized 20 invention patents of China. He gave Plenary and Invited talks by 10 times in international and domestic conference.
Microwave Plasma and Terahertz Physics
Breakdown is the major limitation of high power microwave power. Secondary electron multipactor is the key factor triggering breakdown. The mechanism of gas desorption triggerred by multipactor and methods of periodic surface profile and resonant magnet on suppressing multipactor are reported.
The recent developments of Terahertz(THz) wave sources are discussed, especially for traveling wave vacumm tubes, and nonlinear optical difference frequency generation. Ultrafast ps THz switches with low pump fluence based on high photoconductivity of nm film metasurfaces are reported. Pixelated frequency-agile THz metasurfaces for molecular fingerprint sensing are introduced. Calibration-free, high-precision THz sensors for monitoring cancer are reported. We found Terahertz wave enhances permeability of the voltage-gated ion channel, and nonthermally controlls the neuronal signal and behavior, and accelerates associative learning.