No.37

December, 2004

Headline News Basic Research

Biotechnology

Earth Science
Environmental Protection International Cooperation Briefs Visits & Exchanges

Basic Research

Trapping of single-ions Successfully Realized

The realization of laser cooling and trapping of the ions has finally brought about the isolated system in a complete "static state", which has created conditions for preparing quantum state of various forms of atomic systems and precision measurement. The Wuhan Institute of Physics and Mathematics has done tremendous fundamental work in fields of theory
and experimental research regarding laser cooling and trapping of the ions. In recent years, a research group on ion trapping headed by Prof. Kelin Gao launched research on laser cooling and trapping of a few-ions and single-ions. After years of hard work, the group has improved and developed various "bottle-neck" experimental technology for various trapping units and realized the trapping of a few-ions and single-ions and the Doppler cooling. They have observed signals of quantum transition of single-ions through stimulation of the titanium sapphire laser 729nm (42S1/2-32D5/2) and have thus
successfully realized cooling and trapping of single-ions. Based on such achievements, the first experimental platform for physical research based on single-atom level.

Breakthrough in Research of Two-dimension Cobalt Oxide

In recent years, the research on various cobalt oxides has attracted extensive attention of scientists, which is mainly because the super-conductivity in MaxCoO2-H2O with two dimensional triangular lattice was discovered. One of the very important materials is Sr2CoO4, which has the same two dimensional square lattice structure as the typical high-temperature super-conductivity materials.

Prof. Zhong Fang from the Institute of Physics, CAS cooperated with Prof. Y. Koura from the Tokyo University of Japan has made a specific study of a series of physical properties of this material and found that this material has no super-conductivity, but has very good ferromagnetism. Detailed calculation of its electronic structure demonstrates that Co in the system has an intermediate spin state. The result of calculation can give a good explanation about the observed photo-electricity conductivity of anisotropy.

This finding was published in the Physical Review Letter 93, 167202 (2004).

Breakthrough in Research on GaN-based Laser Diodes

On Nov. 16, a breakthrough was announced regarding the successful development of GaN-based laser diodes, which is a major project of the national 863 program undertaken by the Institute of Semiconductor of CAS. The GaN-based laser Diode with independent intellectual property was developed and fabricated for the first time in mainland China after tackling a series of technological difficulties, such as design of the device structure, material growth, cleavage of the cavity mirror and test analysis. The laser Diode adopts multi-quantum wells with gain waveguide structure. The lasing wavelength is 410nm, strip width 5m, and strip length 800m. The threshold current density is about 5KA/cm2. This achievement marked the research on GaN-based opto-electronic materials and devices have paralleled with the International advanced level.

"Daniel C. Tsui Lectures" Started in Institute of Physics

Recently, the Institute of Physics, CAS invited Prof. Nai-Phuam Ong, a world-famous physicist, to pay a visit and give a lecture in the Institute and thus made the "Daniel C. Tsui Lectures". More than 200 research staffs and postgraduates listened to his lecture.

Daniel C. Tsui, Nobel Prize laureate of 1998 in Physics, is professor of the Princeton University in the U.S. On his visit to the Institute of Physics in Dec. 2003, he expressed his great expectation on the Chinese physics and the development of the Institute of Physics. He showed more concern about the development of the Institute and would spend more efforts to help with education of the Chinese young talents in physics. Through consultation, it was decided to establish "Daniel C. Tsui Lectures", with which Nobel Prize laureates or internationally first-rank physicists will be invited to pay a short visit to the institute for academic exchange, and to provide guidance and evaluation on the research of the Institute of Physics.

Chinese-German Forum on Fundamental and Technological Perspectives of Nanoscience Sponsored by Institute of Physics

The Chinese-German Forum on Fundamental and Technological Perspectives of Nanoscience is convened in the Institute of Physics on Sept 26.

Prof. Sishen Xie, member of CAS and research fellow of the Institute of Physics chaired the forum. Prof. Harald Fuchs from the Munster University, Germany gave a lecture entitled Fundamental and Perspectives from Nanosicence to Nano Technology. Prof. Helmut Zacharias and Prof. Lifeng Chi from the Munster University, Germany, Prof. Gerhard Wilde from the Karlsruhe Research Center, Prof. Hans Albert Kolb and Prof. Peter Von Blanckenhagen from the Hannover University gave wonderful lectures at the symposium. More than 100 people attended the symposium.

Other Issues
Fifteenth Issue (Spring 2000)
Sixteenth Issue (Summer 2000)
Seventeenth Issue (Autumn 2000)
Eighteenth Issue (Winter 2000)
Nineteenth Issue (Spring 2001)
Twentith Issue (Summer 2001)
Twenty-first Issue (Autumn 2001)
Twenty-second Issue (Winter 2001)
Twenty-third Issue (Spring 2002)
Twenty-forth Issue (Summer 2002)
Twenty-fifth Issue (Autumn 2002)
Twenty-sixth Issue (Winter 2002)
Twenty-seventh Issue (Spring, 2003)
Twenty-eighth Issue (June, 2003)
Twenty-nineth Issue (August, 2003)
Thirtieth Issue (October, 2003)
Thirty-first Issue (December, 2003)
Thirty-second Issue (February, 2004)
Thirty-third Issue (April, 2004)
Thirty-fourth Issue (June, 2004)
Thirty-fifth Issue (August, 2004)
Thirty-sixth Issue (October, 2004)

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