| Superconductors Essay, Research Paper
Type II superconductors are much different from Type I superconductors
because Type II superconductors gradually become superconducting
materials as opposed to at a certain temperature as Type I superconductors
do. As opposed to Type I superconductors, Type II superconductors are
mostly metallic compounds and alloys. The major exceptions to this are
the elements niobium, technetium, and vanadium. These are pure elements
that are Type II superconductors at sufficiently low temperatures.
Type II superconductors have much higher critical temperatures than Type I
superconductors. Also opposite to Type I superconductors, Type II
superconductors do allow some penetration by an external magnetic field.
Scientists are still trying to understand what makes Type II
superconductors have critical temperatures so much higher than those of the Type I
superconductors. It is thought that it is related to the planar
layering in the structure of the crystal. The highest temperature Type II
superconductor is a perovskite with a critical temperature of 138 K, an
incredibly high temperature for a superconductor. This compound is
Hg0.8Tl0.2Ba2Ca2Cu3O8.33.
The final type of superconductors is the atypical superconductors.
These superconductors are made by fullerides. Fullerides or fullerenes
are spherical molecules that are made of sixty carbon atoms. This type
of superconductors do not have the high critical temperatures that the
Type II superconductors do. Like ceramic superconductors, fullerenes
are a fairly recent discovery. They were accidentally discovered in
1985 by Robert F. Curl, Jr. and Richard E. Smalley of Rice University in
Houston and Professor Sir Harold W. Kroto of the University of Sussex in
Bighton, England. Because this material is fairly new, not much is
known about fullerides or why exactly they can superconduct. Fullernenes
are technically part of a larger family of organic conductors, which
include molecular salts, polymers, and pure carbon systems. The
molecular salts, often referred to as ?molecular? superconductors, are the
organic molecules that exhibit superconductive properties at very low
temperatures. Organic superconductors are composed of an electron donor
(the planar organic molecule) and an electron acceptor (a non-organic
anion). In 1993, Bob Cava, currently at Princeton University, and Bell
Labs discovered ?Borocarbides? which are one of the least-understood
superconductor systems of all. These superconductors raise questions about
the always-assumed theory that superconductors cannot be formed from
ferromagnetic transition metals – like iron, cobalt or nickel. With all
the questions that these superconductors arouse, atypical
superconductors are the most mysterious of all the other types.
The discovery of superconducting materials has opened the doors to
endless possibilities in technological advancements. Many transportation
vehicles such as trains are beginning to take advantage of
superconductors? magnetic-levitation ability. Using strong superconducting
magnets, these vehicles can be made to ?float? and virtually eliminate
friction between the train and its tracks. In biomagnetism, doctors can use
superconductors to save lives through the usage of impinging a strong
superconductor-derived magnetic field into the body and using a computer
to detect the energy released to view the inside of the human body.
This medical process is called Magnetic Resonance Imaging (MRI) and has
become crucial in determining what is wrong with the internal systems of
the body. Superconductors make s being able to accelerate sub-atomic
particles to nearly the speed of light, which is effective in
construction. Because of the little to no resistance of electric current in
superconductors, they have become extremely useful in electric generators
and other electrical devices. Superconducting wire has been found to be
more than ninety-nine percent more efficient than the typical copper
wires. ?Petaflop? computers being newly tested which uses
superconductors to have a thousand trillion floating operations per second, speeding
up the computer immensely. Superconductors have also been found to be
extremely effective in satellites and many military applications as
well. The list of possible uses of superconductors goes on and on, and
with the constant new discoveries and developments, the possibilities are
endless.
Through the discovery of superconductors, many technological
advancements were brought about. The science of superconductivity is relatively
new and much still remains unknown. The limits of superconductivity
have not yet been reached, and what theories that are in existence are
still under constant scrutiny. There are three main types of
superconductors that are widely used. From construction to transportation, from
electricity to computer, from military applications to the medical
field, superconductors have become immensely important in many aspects of
today?s world. Everyday, new things are discovered and a new technology
improved; this is just the beginning of superconductor?s abilities.
The possibilities are endless and the future looks bright for this
exciting material.
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