AWARDEE OF PHYSICS PRIZE

WANG XUN

Abstract

Professor Wang Xun, a physicist, was born in Shanghai on 23 April 1934.  He    completed his undergraduate study in 1956 in the Physics Department of Fudan    University.  Later he was a graduate student in condensed matter physics supervised by Professor Xie Xide from 1956 to 1960.  After graduation, he became a faculty of Fudan University and was promoted as a lecturer, associate professor, and full professor in 1963, 1978, and 1984, respectively.  In 1980, he was a visiting professor at the University of Wisconsin-Milwaukee, USA.  He served as the director of the Surface Physics Laboratory (National Key Laboratory) of Fudan University from 1990 to 1997, and was granted as a Chair Professor of Fudan University in 1996.  His professional positions include the Member of the Semiconductor Commission of the International Union of Pure and Applied Physics (1993-1999), Advisory Editorial Board of the international journal <Surface Science>, Council member of Chinese Physical Society, and the President of Shanghai Physical Society (1997-1999).
His current research fields are Silicon-based Low Dimensional Quantum Structures,    Surfaces and Interfaces of Semiconductors.  His major scientific contributions are    focused in the following areas:
1.Surfaces of semiconductors
He studied the surface atomic and electronic structures of InP polar surfaces and Si(100) surfaces.  Based on the experimental measurements using varies electron spectroscopic techniques and the theoretical calculations, he proposed an atomic relaxation model for InP (111)(1×1) surface and a missing row-dimer model for InP(100)(4×2) surface.  He is the first one who proposed the surface atomic structures for InP polar surfaces.  On Si(100) clean surface, he is the first person who discovered a new surface reconstruction c(4×4).
2.Light-emitting porous silicon
He achieved the blue light emission from porous silicon for the first time in 1992, which attracted a great deal of attention in the porous silicon community and was highlighted in the 1993 Fall Meeting of the American Materials Research Society.
He observed the infrared up-conversion effect of porous silicon and attributed it to the enhancement of third order optical susceptibility of porous silicon caused by the quantum confinement.  This is the first experimental fact verifying that the porous silicon is a kind of nonlinear optical material.
3.Silicon/Germanium superlattices and quantum dots
He achieved the epitaxial growth of high quality Si/Ge superlattices with very flat interfaces and high thickness uniformity.  The x-ray diffraction spectra revealed up to 17th order satellite peaks and the Raman scattering showed the appearance of 9th order folded phonon peak, that have never been reported in previous work for the same sample structures.
He established the measurements of the physical properties of the SiGe quantum    wells by using the ordinary electrical methods such as the deep level transient    spectroscopy, capacitance-voltage method and admittance spectroscopy.  He presented    and achieved a smart idea of studying the Coulomb charging effect in Ge quantum dots    by admittance spectroscopy at temperatures above the liquid nitrogen temperature.
He collaborated with other institutions to successfully fabricate several kinds of novel SiGe devices, including the infrared detector, heterojunction bipolar transistor, optical waveguide, directional coupler, optical switch and modulator.
He published more than 130 papers in the international journals and presented 21 invited talks on the international conferences and workshops.  He won 4 class B Awards and 3 class C Awards for Progress of Science and Technology granted by the State Education Commission of China.  Also, he was granted the 1997 Ye Qi-sun Physics    Award by the Chinese Physical Society , and the 1996 Class B Award by the Guang-    Hua Science and Technology Foundation.