Superconductors is technology of future. It has application in all branch of science that works with energy transfer. One of the main applications of superconductors is obtaining superstrong magnetic fields. It can really change the world but not now because we have some of problem. First- what is a superconductor?
Superconductor is an element, inter-metallic alloy, or compound that will conduct electricity without resistance below a certain temperature. Resistance is undesirable because it produces losses in the energy flowing through the material.
Once set in motion, electrical current will flow forever in a closed loop of superconducting material — making it the closest thing to perpetual motion in nature. Scientists refer to superconductivity as a ‘macroscopic quantum phenomenon’.
Superconductors, materials that have no resistance to the flow of electricity, are one of the last great frontiers of scientific discovery. Not only have the limits of superconductivity not yet been reached, but the theories that explain superconductor behavior seem to be constantly under review. In 1911 superconductivity was first observed in mercury by Dutch physicist Heike Kamerlingh Onnes of Leiden University (shown above). When he cooled it to the temperature of liquid helium, 4 degrees Kelvin (-452F, -269C), its resistance suddenly disappeared. The Kelvin scale repsents an «absolute» scale of temperature. Thus, it was necessary for Onnes to come within 4 degrees of the coldest temperature that is theoretically attainable to witness the phenomenon of superconductivity. Later, in 1913, he won a Nobel Prize in physics for his research in this area.
So, why we can’t use the superconductors right now? An element becomes superconductor in extremely low temperatures. Fine, if the scientists can fix it, how it can help normal people? Except economical a power supply,
Superconductors have one more interesting property, that people can use in future.
The next great milestone in understanding how matter behaves at extreme cold temperatures occurred in 1933. German researchers Walther Meissner and Robert Ochsenfeld discovered that a superconducting material will repel a magnetic field. A magnet moving by a conductor induces currents in the conductor. This is the principle on which the electric generator operates. But, in a superconductor the induced currents exactly mirror the field that would have otherwise penetrated the superconducting material — causing the magnet to be repulsed. This phenomenon is known as strong diamagnetism and is today often referred to as the «Meissner effect» (an eponym). The Meissner effect is so strong that a magnet can actually be levitated over a superconductive material.
Many of people are looked ‘back to the future’ or ‘THE FIFTH ELEMENT’. One think- flying car. Though some of people who watch ‘back to the future’ more like the flying skateboard, that Marty McFly has. Both of this dream can become usually thing if we will learn create superconductivity in normal temperature. Theoretically it’s a very simple. For this we have to buld up the road consist of superconductors and cars or skateboard’s bottom consist of very powerful magnet. And they will be levitate.
In subsequent decades other superconducting metals, alloys and compounds were discovered. In 1941 niobium-nitride was found to superconduct at 16 K. In 1953 vanadium-silicon displayed superconductive properties at 17.5 K. And, in 1962 scientists at Westinghouse developed the first commercial superconducting wire, an alloy of niobium and titanium (NbTi). High-energy, particle-accelerator electromagnets made of copper-clad niobium-titanium were then developed in the 1960s at the Rutherford-Appleton Laboratory in the UK, and were first employed in a superconducting accelerator at the Fermilab Tevatron in the US in 1987.
The first widely-accepted theoretical understanding of superconductivity was advanced in 1957 by American physicists John Bardeen, Leon Cooper, and John Schrieffer (above). Their Theories of Superconductivity became know as theBCS theory — derived from the first letter of each man's last name — and won them a Nobel prize in 1972. The mathematically-complex BCS theory explained superconductivity at temperatures close to absolute zero for elements and simple alloys. However, at higher temperatures and with different superconductor systems, the BCS theory has subsequently become inadequate to fully explain how superconductivity is occurring.
Another significant theoretical advancement came in 1962 when Brian D. Josephson (above), a graduate student at Cambridge University, pdicted that electrical current would flow between 2 superconducting materials — even when they are separated by a non-superconductor or insulator. His pdiction was later confirmed and won him a share of the 1973 Nobel Prize in Physics. This tunneling phenomenon is today known as the «Josephson effect» and has been applied to electronic devices such as the SQUID, an instrument capabable of detecting even the weakest magnetic fields. (Below SQUID graphic courtesy Quantum Design.)
The 1980's were a decade of unrivaled discovery in the field of superconductivity. In 1964 Bill Little of Stanford University had suggested the possibility of organic (carbon-based) superconductors. The first of these theoretical superconductors was successfully synthesized in 1980 by Danish researcher Klaus Bechgaard of the University of Copenhagen and 3 French team members. (TMTSF)2PF6 had to be cooled to an incredibly cold 1.2K transition temperature (known as Tc) and subjected to high pssure to superconduct. But, its mere existence proved the possibility of «designer» molecules — molecules fashioned to perform in a pdictable way.
Then, in 1986, a truly breakthrough discovery was made in the field of superconductivity. Alex Müller and Georg Bednorz (above), researchers at the IBM Research Laboratory in Rüschlikon, Switzerland, created a brittle ceramic compound that superconducted at the highest temperature then known: 30 K. What made this discovery so remarkable was that ceramics are normally insulators. They don't conduct electricity well at all. So, researchers had not considered them as possible high-temperature superconductor candidates. The Lanthanum, Barium, Copper and Oxygen compound that Müller and Bednorz synthesized, behaved in a not-as-yet-understood way. The discovery of this first of the superconducting copper-oxides (cuprates) won the 2 men a Nobel Prize the following year. It was later found that tiny amounts of this material were actually superconducting at 58 K, due to a small amount of lead having been added as a calibration standard — making the discovery even more noteworthy.
The first company to capitalize on high-temperature superconductors was Illinois Superconductor (today known as ISCO International), formed in 1989. This amalgam of government, private-industry and academic interests introduced a depth sensor for medical equipment that was able to operate at liquid nitrogen temperatures (~ 77K).
Also in 2001 a material that had been sitting on laboratory shelves for decades was found to be an extraordinary new superconductor. Japanese researchers measured the transition temperature of magnesium diboride at 39 Kelvin — far above the highest Tc of any of the elemental or binary alloy superconductors. While 39 K is still well below the Tc's of the «warm» ceramic superconductors, subsequent refinements in the way MgB2 is fabricated have paved the way for its use in industrial applications. Laboratory testing has found MgB2 will outperform NbTi and Nb3Sn wires in high magnetic field applications like MRI.
The most recent «family» of superconductors to be discovered is the «pnictides». These iron-based superconductors were first observed by a group of Japanese researchers in 2006. Like the high-Tc copper-oxides, the exact mechanism that facilitates superconductivity in them is a mystery. However, with Tc's over 50K, a great deal of excitement has resulted from their discovery.
There are a lot of types of superconductors and their application long more wider then super battery and child’s dream.
Magnetic-levitation is an application where superconductors perform extremely well. Transport vehicles such as trains can be made to «float» on strong superconducting magnets, virtually eliminating friction between the train and its tracks. Not only would conventional electromagnets waste much of the electrical energy as heat, they would have to be physically much larger than superconducting magnets. A landmark for the commercial use of MAGLEV technology occurred in 1990 when it gained the status of a nationally-funded project in Japan. The Minister of Transport authorized construction of the Yamanashi Maglev Test Line which opened on April 3, 1997. In December 2003, the MLX01 test vehicle (shown above) attained an incredible speed of 361 mph (581 kph).
An area where superconductors can perform a life-saving function is in the field of biomagnetism. Doctors need a non-invasive means of determining what's going on inside the human body. By impinging a strong superconductor-derived magnetic field into the body, hydrogen atoms that exist in the body's water and fat molecules are forced to accept energy from the magnetic field. They then release this energy at a frequency that can be detected and displayed graphically by a computer.
Probably the one event, more than any other, that has been responsible for putting «superconductors» into the American lexicon was the Superconducting Super-Collider project planned for construction in Ellis county, Texas. Though Congress cancelled the multi-billion dollar effort in 1993, the concept of such a large, high-energy collider would never have been viable without superconductors.
Among emerging technologies are a stabilizing momentum wheel (gyroscope) for earth-orbiting satellites that employs the «flux-pinning» properties of imperfect superconductors to reduce friction to near zero. Superconducting x-ray detectors and ultra-fast, superconducting light detectors are being developed due to their inherent ability to detect extremely weak amounts of energy. Already Scientists at the European Space Agency (ESA) have developed what's being called the S-Cam, an optical camera of phenomenal sensitivity. And, superconductors may even play a role in Internet communications soon. In late February, 2000, Irvine Sensors Corporation received a $1 million contract to research and develop a superconducting digital router for high-speed data communications up to 160 Ghz. Since Internet traffic is increasing exponentially, superconductor technology may be called upon to meet this super need. Irvine Sensors speculates this router may see use in facilitating Internet2.
And that is a little part of possible applications.
So, superconductors is a promising sector, that can gived people much of that they want. Superconductors is a future.
