Academician Maw-Kuen Wu Receives
Humboldt Research Award

A team mainly composed of researchers from the Institute of Physics recently discovered that at least three different kinds of iron(Fe)-vacancy order exist in one type of Fe-based superconductor, and showed that at least one of these three Fe-vacancy orders is non-superconducting and magnetic at low temperature. This new finding is exciting as physicists still do not know what causes some complex multicomponent materials to become superconducting, a gap in knowledge that is limiting real-life application of the phenomenon. The discovery was published in the Proceedings of the National Academy of Sciences (PNAS) on January 7.

A superconductor is a material that can conduct electricity or transport electrons from one atom to another with no resistance. Superconductivity typically occurs in certain materials when they are cooled below a critical temperature. For many years, the highest critical temperature (superconducting phase transition temperature) known for a superconductor was about 23 K (minus 250°C, or minus 418°F), meaning that superconducting materials needed to be cooled by liquid helium for use, a process so complicated and expensive that it ruled out the practical use of superconductors in most applications. However, in 1986 a high temperature superconducting material – lanthanum barium copper oxide – was discovered. Then in 2008, more high temperature superconductors that are Fe-based were discovered. These so-called “high temperature” superconductors, especially the copper oxide system, have critical temperatures in a range up to around 130 K (minus 143°C, or minus 226°F), and were greeted with great excitement among physicists and potential manufacturers because they can be maintained in the superconducting state with liquid nitrogen (77 K) meaning that cooling the superconductor for real-life applications becomes much more feasible. However, although physicists believe they understand the mechanisms governing the earlier low-temperature superconductors, the mechanisms that determine high-temperature superconductivity – the origin of the superconductivity – remain a mystery. 

High-temperature superconductors exhibit an array of peculiar and unexpected behavior. Among the unresolved questions surrounding high temperature superconductor research are the exact chemical stoichiometry of superconducting compounds, why the superconducting transition temperatures exist over such a wide range in a single material system, and whether and how the superconductivity of Fe-based superconductors is related to the magnetism that normally comes with Fe element. All these questions have become the focus of current research in Fe-based superconductors.

In the current study, the research team led by Academician Maw-Kuen Wu (Distinguished Research Fellow and the President of National Dong Hwa University), in collaboration with Professor Fu-Rong Chen of National Tsing Hua University, and Professor Dirk Van Dyck of University of Antwerp in Belgium showed that at least three different kinds of iron(Fe)-vacancy order exist in one type of Fe-based superconductor, an FeSe compound, and showed that at least one of these three Fe-vacancy orders is non-superconducting and magnetic at low temperature. In 2008, Academician Wu’s team discovered superconductivity in the FeSe compound for the first time. They used the same compound in their current study.

The new study advances the field because, firstly, it is generally accepted that the origin of high temperature superconductivity is an antiferromagnetic insulating parent (original, non-superconducting) phase, which leads to the destruction of magnetism and then the appearance of superconductivity after the introduction of mobile electrons (or holes). The current new findings provide, for the first time, mapping of an exact phase diagram for the FeSe superconducting system.  Secondly, the research discovery shows the presence of new types of Fe-vacancy order in Fe-based materials. This result gives scientists a better opportunity to understand the correlation between superconductivity and Fe-vacancy. In fact, this information may provide a new direction for the understanding of superconducting phenomena observed in all high temperature superconductors including non-Fe systems such as copper oxide systems.

Superconductors are already used in several applications, notably magnetic resonance imaging (MRI) used in hospitals, maglevs (high-speed magnetic levitation trains), particle accelerator applications and NMR spectroscopy.

If researchers can overcome the issues of cost, refrigeration and reliability that limit current superconducting materials, superconductors may have the potential to revolutionize electrical engineering with more efficient motors and generators and lossless power transmission. Promising future applications would include zero-loss electrical power lines, high-performance smart grids, electric power transmission, radar, transformers, power storage devices, high energy physics, high-end computing, nanoscopic materials and superconducting magnetic refrigeration.

The complete article entitled "Fe-vacancy order and superconductivity in tetragonal β-Fe1-xSe" can be found at the PNAS website at: http://www.pnas.org/content/111/1/63.abstract.

The complete list of authors is: Ta-Kun Chen, Chung-Chieh Chang, Hsian-Hong Chang, Ai-Hua Fang, Chih-Han Wang, Wei-Hsiang Chao, Chuan-Ming Tseng, Yung-Chi Lee, Yu-Ruei Wu, Min-Hsueh Wen, Hsin-Yu Tang, Fu-Rong Chen, Ming-Jye Wang, Maw-Kuen Wu and Dirk Van Dyck.

Media Contacts:
Academician Maw-Kuen Wu, Distinguished Research Fellow, Institute of Physics, Academia Sinica and the President of National Dong Hwa University (Tel)+886-3- 863-2001
Ms. Mei-hui Lin, Office of the Director General, Academia Sinica mhlin313@gate.sinica.edu.tw
(Tel) +886-2-2789-8821 (Fax) +886-2-2782-1551 (M) 0921-845-234
Ms. Pearl Huang, Office of the Director General, Academia Sinica pearlhuang@gate.sinica.edu.tw
(Tel) +886-2-2789-8820 (Fax) +886-2-2782-1551 (M) 0912-831-188
Prof. Ko-Ching Tung, Public Relation Office, National Dong Hwa University kctung@mail.ndhu.edu.tw
(Tel) +886-3-8632011 (Fax) +886-3-8632000

Release Unit : Office of the Director General
2014-02-18 09:06:34





Academician Maw-Kuen Wu Receives
Humboldt Research Award
Humboldt Research Award
Academician Maw-Kuen Wu, Distinguished Research Fellow and Director of the Institute of Physics, was recently awarded a Humboldt Research Award by the Alexander von Humboldt Foundation in recognition of his accomplishments in research and teaching. Academician Wu received the award at an annual symposium in Bamberg, Germany on March 21, 2010. 
The Humboldt Research Award honors the achievements of researchers whose fundamental discoveries, insights or new theories have had a lasting impact on their field of specialization. Award winners are invited to spend up to a year carrying out research projects they have chosen themselves in cooperation with colleagues in Germany. Nominations for the award must be made by academics in Germany; it is not possible to apply directly.
Academician Wu specializes in superconductivity and magnetism. In addition to his posts at Academia Sinica, he has been a faculty member of the Department of Physics at National Tsing Hua University since 1995. He is a member of US National Academy of Science and the Academy of Sciences for the Developing World (TWAS). Academician Wu has held several governmental posts. Since 2006, he has served as the director general of Taiwan National Science and Technology Program for Nanoscience and Nanotechnology. He was the Minister of the ROC National Science Council between 2004 and 2006, subsequent to his appointment as the council’s deputy minister from 2000 to 2002. 
The Alexander von Humboldt Foundation is a government-funded foundation that promotes cooperation between German institutes of higher education and leading academies around the world. It was first established in 1860 in honor of the German nature researcher and explorer, Alexander von Humboldt; however, it ceased operation on several occasions during the turbulence of the early 20th century. Today’s Alexander von Humboldt Foundation was re-established by the Federal Republic of Germany in 1953. Currently, every year the foundation enables more than 2,000 researchers from all over the world to spend time researching in Germany. The Foundation also maintains a network of over 24,000 scientists from more than 130 countries worldwide.

Academicians Awarded Italian Science for Peace Prize
Ettore Majorana-Erice-Science for Peace Prize 2007

Academician and Director of the Academician Paul Ching-Wu Chu, and Institute of Physics Maw-Kuen Wu have been awarded the "Ettore Majorana – Erice – Science for Peace Prize" for playing leading roles in the advancement of science for peaceful purposes. 

Dr. Chu and Dr. Wu were awarded the prize: "For their discovery of Y Ba2 Cu3 superconductor, the first system with transition temperature exceeding 77 degrees Kelvin, and for their subsequent contributions in researches of many novel superconducting systems. Dr. Wu and Dr. Chu are truly dedicated to the pursuit of truth and to the education of young scientists, and both of them embody the best of the spirit of Erice." 

A ceremony will be hosted by the Pontifical Academy of Sciences in the Vatican in Rome on 17th December to bestow the award. 

The "Ettore Majorana – Erice – Science for Peace Prize" was established by the Sicilian Parliament. It recognizes the impressive achievements of the World Federation of Scientists (WFS), under the auspices of the Ettore Majorana Foundation and the Centre for Scientific Culture. Recipients are elected by the World Federation of Scientists. 

The annual award includes a cash prize to assist recipients in their efforts to "promote science and peace throughout the world." The first edition of the prize was awarded in 1990. The prize is named after Ettore Majorana, an early 20th century theoretical physicist most well-known for his ideas about neutrino masses and also for his mysterious disappearance in 1938. Majorana was born in Sicily in 1906. 

The WFS was founded in 1973. Currently over 10,000 scientists from over 110 countries are members of the federation. The most famous accomplishment of the WFS is the establishment of the ‘Erice Statement’ in 1982 which opposes the use of science for militaristic means and promotes the use of science for peace. 

Dr. Chu is currently the President of the Hong Kong University of Science & Technology. He also holds the T.L.L. Temple Chair of Science at the University of Houston and is Executive Director of the Texas Center for Superconductivity. 

Dr. Wu was made an Academia Sinica Academician in 1998. He is currently a Distinguished Research Fellow and Director, Institute of Physics. Over the course of his career he has received several awards including the Comstock Prize from The National Academy of Sciences (1988), the NASA Special Awards (1988), Tamkang Golden Eagle Award from Tamkang University (1989), the Bernd T. Mattias Prize (1994), the Outstanding Scholar Award from the Foundation for the Advancement of Outstanding Scholarship (1995), Member, Asia-Pacific Academy of Material NSTP for Nanoscience and Nanotechnology (1998). In 2004, he was made a Foreign Associate, of the U.S. National Academy of Sciences in 2004 and a Fellow of the Academy of Sciences for the Developing World (TWAS). 

Over the course of his career he has received the Leroy Randall Grumman Medal (1987), the Comstock Award (1988), National Medal of Science (1988), International Prize for New Materials (1989), the Texas Instruments Founder's Prize (1990), the Bernd Matthias Materials Prize (1994), the Freedoms Foundation National Award (2001), and the Russian Academy of Engineering (2005) Dr. Chu became a member of the U.S. National Academy of Sciences and the American Academy of Arts and Sciences in1989 and a member of the Chinese Academy of Sciences in 1996. 

Physics Institute Reports Less Toxic,
Easier-to-handle Iron-based Superconductor

The research team led by Maw-Kuen Wu , Director of the Institute of Physics, reported a new iron-based superconductor (PbO type structure α-FeSe) which is less toxic and easier to handle than previous research from Japan. Both reports overthrew the concept which the iron-based compounds could not be the high-temperature superconducting materials. Proceedings of the National Academy of Sciences of the United States of America (PNAS, vol. 105) published this achievement on September 23, 2008.  pdf


c2008 Company Institute of Physics, Superconductor Lab