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High-temperature Superconductivity
High-temperature superconductors (abbreviated high-c or HTS) are defined as materials with critical temperature (the temperature below which the material behaves as a superconductor) above , the boiling point of liquid nitrogen. They are only "high-temperature" relative to previously known superconductors, which function at even colder temperatures, close to absolute zero. The "high temperatures" are still far below ambient (room temperature), and therefore require cooling. The first break through of high-temperature superconductor was discovered in 1986 by IBM researchers Georg Bednorz and K. Alex Müller. Although the critical temperature is around , this new type of superconductor was readily modified by Ching-Wu Chu to make the first high-temperature superconductor with critical temperature . Bednorz and Müller were awarded the Nobel Prize in Physics in 1987 "for their important break-through in the discovery of superconductivity in ceramic materials". Most high-c mate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnesium Diboride
Magnesium diboride is the inorganic compound with the formula MgB2. It is a dark gray, water-insoluble solid. The compound has attracted attention because it becomes superconducting at 39 K (−234 °C). In terms of its composition, MgB2 differs strikingly from most low-temperature superconductors, which feature mainly transition metals. Its superconducting mechanism is primarily described by BCS theory. Superconductivity Magnesium diboride's superconducting properties were discovered in 2001. Its critical temperature (''T''c) of is the highest amongst conventional superconductors. Among conventional ( phonon-mediated) superconductors, it is unusual. Its electronic structure is such that there exist two types of electrons at the Fermi level with widely differing behaviours, one of them ( sigma-bonding) being much more strongly superconducting than the other ( pi-bonding). This is at odds with usual theories of phonon-mediated superconductivity which assume that all el ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chu Ching-wu
Paul Ching Wu Chu (; born February 12, 1941) is a Chinese-American physicist specializing in superconductivity, magnetism, and dielectrics. He is a Professor of physics and T.L.L. Temple Chair of Science in the Physics Department at the University of Houston College of Natural Sciences and Mathematics. He was the President of the Hong Kong University of Science and Technology from 2001 to 2009. In 1987, he was one of the first scientists to demonstrate high-temperature superconductivity. Early life Chu was born in Changsha, Hunan, Republic of China in 1941. Chu's family was from Taishan, Guangdong. Chu spent his childhood in Taiwan. Education In 1958, Chu graduated from Taiwan Provincial Cingshuei high school. In 1962, Chu earned his Bachelor of Science degree from National Cheng Kung University in Taiwan. In 1965, Chu earned his Master of Science degree from Fordham University. In 1968, Chu earned his Ph.D. degree from the University of California, San Diego. Career ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Switzerland
; rm, citad federala, links=no). Swiss law does not designate a ''capital'' as such, but the federal parliament and government are installed in Bern, while other federal institutions, such as the federal courts, are in other cities (Bellinzona, Lausanne, Lucerne, Neuchâtel, St. Gallen a.o.). , coordinates = , largest_city = Zurich , official_languages = , englishmotto = "One for all, all for one" , religion_year = 2022 , religion_ref = , religion = , demonym = , german: link=no, Schweizer/Schweizerin, french: link=no, Suisse/Suissesse, it, svizzero/svizzera or , rm, Svizzer/Svizra , government_type = Federal assembly-independent directorial republic , leader_title1 = Federal Council , leader_name1 = , leader_title2 = , leader_name2 = Viktor Rossi , legislature = Federal Assembly , upper_house = Counci ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zurich
Zurich (; ) is the largest city in Switzerland and the capital of the canton of Zurich. It is located in north-central Switzerland, at the northwestern tip of Lake Zurich. , the municipality had 443,037 inhabitants, the urban area 1.315 million (2009), and the Zurich metropolitan area 1.83 million (2011). Zurich is a hub for railways, roads, and air traffic. Both Zurich Airport and Zurich's main railway station are the largest and busiest in the country. Permanently settled for over 2,000 years, Zurich was founded by the Romans, who called it '. However, early settlements have been found dating back more than 6,400 years (although this only indicates human presence in the area and not the presence of a town that early). During the Middle Ages, Zurich gained the independent and privileged status of imperial immediacy and, in 1519, became a primary centre of the Protestant Reformation in Europe under the leadership of Huldrych Zwingli. The official language of Zurich is Germ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Niobium–tin
Niobium–tin is an intermetallic compound of niobium (Nb) and tin (Sn), used industrially as a type II superconductor. This intermetallic compound has a simple structure: A3B. It is more expensive than niobium–titanium (NbTi), but remains superconducting up to a magnetic flux density of , compared to a limit of roughly 15 T for NbTi. Nb3Sn was discovered to be a superconductor in 1954. The material's ability to support high currents and magnetic fields was discovered in 1961 and started the era of large-scale applications of superconductivity. The critical temperature is . Application temperatures are commonly around , the boiling point of liquid helium at atmospheric pressure. In April 2008 a record non-copper current density was claimed of 2,643 A mm−2 at 12 T and 4.2 K. History Nb3Sn was discovered to be a superconductor in 1954, one year after the discovery of V3Si, the first example of an A3B superconductor. In 1961 it was discovered tha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Niobium–titanium
Niobium–titanium (Nb-Ti) is an alloy of niobium and titanium, used industrially as a type II superconductor wire for superconducting magnets, normally as Nb-Ti fibres in an aluminium or copper matrix. Its critical temperature is about 10 kelvins. The high-critical-magnetic-field, high-critical-supercurrent-density properties of Nb-Ti was discovered in 1962 at Atomics International by T. G. Berlincourt and R. R. Hake. Nb-Ti alloys are notable for their easy workability and thus affordability, distinguishing them from other superconducting materials. Nb-Ti alloys have a maximal critical magnetic field of about 15 teslas, and thus are suitable for fabricating supermagnets capable of generating magnetic fields up to about 10 teslas. For higher magnetic fields, higher-performance but difficult to fabricate and thus more expensive superconductors such as niobium–tin are commonly employed. The global superconductivity market amounted to about five billion euros in 2014. MRI (M ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Niobium
Niobium is a chemical element with chemical symbol Nb (formerly columbium, Cb) and atomic number 41. It is a light grey, crystalline, and ductile transition metal. Pure niobium has a Mohs hardness rating similar to pure titanium, and it has similar ductility to iron. Niobium oxidizes in Earth's atmosphere very slowly, hence its application in jewelry as a hypoallergenic alternative to nickel. Niobium is often found in the minerals pyrochlore and columbite, hence the former name "columbium". Its name comes from Greek mythology: Niobe, daughter of Tantalus, the namesake of tantalum. The name reflects the great similarity between the two elements in their physical and chemical properties, which makes them difficult to distinguish. English chemist Charles Hatchett reported a new element similar to tantalum in 1801 and named it columbium. In 1809, English chemist William Hyde Wollaston wrongly concluded that tantalum and columbium were identical. German chemist Heinrich ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Room-temperature Superconductor
A room-temperature superconductor is a material that is capable of exhibiting superconductivity at operating temperatures above , that is, temperatures that can be reached and easily maintained in an everyday environment. , the material with the highest accepted superconducting temperature is an extremely pressurized carbonaceous sulfur hydride with a critical transition temperature of +15 °C at 267 GPa. On 22 September 2022, the original article reporting superconductivity in the carbonaceous sulfur hydride material was retracted by ''Nature'' journal editorial board due to a non standard, user-defined data analysis, calling into question the scientific validity of the claim. At atmospheric pressure the temperature record is still held by cuprates, which have demonstrated superconductivity at temperatures as high as . Although researchers once doubted whether room-temperature superconductivity was actually achievable, superconductivity has repeatedly been discovered at te ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heike Kamerlingh Onnes
Heike Kamerlingh Onnes (21 September 1853 – 21 February 1926) was a Dutch physicist and Nobel laureate. He exploited the Hampson–Linde cycle to investigate how materials behave when cooled to nearly absolute zero and later to liquefy helium for the first time, in 1908. He also discovered superconductivity in 1911. Biography Early years Kamerlingh Onnes was born in Groningen, Netherlands. His father, Harm Kamerlingh Onnes, was a brickworks owner. His mother was Anna Gerdina Coers of Arnhem. In 1870, Kamerlingh Onnes attended the University of Groningen. He studied under Robert Bunsen and Gustav Kirchhoff at the University of Heidelberg from 1871 to 1873. Again at Groningen, he obtained his master's degree in 1878 and a doctorate in 1879. His thesis was ''Nieuwe bewijzen voor de aswenteling der aarde'' (''tr''. New proofs of the rotation of the earth). From 1878 to 1882 he was assistant to Johannes Bosscha, the director of the Delft Polytechnic, for whom he substituted as le ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Timeline Of Superconductivity From 1900 To 2015
A timeline is a display of a list of events in chronological order. It is typically a graphic design showing a long bar labelled with dates paralleling it, and usually contemporaneous events. Timelines can use any suitable scale representing time, suiting the subject and data; many use a linear scale, in which a unit of distance is equal to a set amount of time. This timescale is dependent on the events in the timeline. A timeline of evolution can be over millions of years, whereas a timeline for the day of the September 11 attacks can take place over minutes, and that of an explosion over milliseconds. While many timelines use a linear timescale—especially where very large or small timespans are relevant -- logarithmic timelines entail a logarithmic scale of time; some "hurry up and wait" chronologies are depicted with zoom lens metaphors. History Time and space, particularly the line, are intertwined concepts in human thought. The line is ubiquitous in clocks in t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
