1.1 Superconductivity
Superconductivity
is the phenomenon in which a material losses all its electrical
resistance and allowing electric current to flow without dissipation
or loss of energy. The atoms in materials vibrate due to thermal
energy contained in the materials: the higher the temperature,
the more the atoms vibrate. An ordinary conductor's electrical
resistance is caused by these atomic vibrations, which obstruct
the movement of the electrons forming the current. If an ordinary
conductor were to be cooled to a temperature of absolute zero,
atomic vibrations would cease, electrons would flow without obstruction,
and electrical resistance would fall to zero. A temperature of
absolute zero cannot be achieved in practice, but some materials
exhibit superconducting characteristics at higher temperatures.
In 1911, the
Dutch physicist Heike Kamerlingh Onnes discovered superconductivity
in mercury at a temperature of approximately 4 K (-269o C). Many
other superconducting metals and alloys were subsequently discovered
but, until 1986, the highest temperature at which superconducting
properties were achieved was around 23 K (-250o C) with the niobium-germanium
alloy (Nb3Ge)
In 1986 George
Bednorz and Alex Muller discovered a metal oxide that exhibited
superconductivity at the relatively high temperature of 30 K (-243o
C). This led to the discovery of ceramic oxides that super conduct
at even higher temperatures. In 1988, and oxide of thallium, calcium,
barium and copper (Ti2Ca2Ba2Cu3O10) displayed superconductivity
at 125 K (-148o C), and, in 1993 a family based on copper oxide
and mercury attained superconductivity at 160 K (-113o C). These
"high-temperature" superconductors are all the more
noteworthy because ceramics are usually extremely good insulators.
Like ceramics,
most organic compounds are strong insulators; however, some organic
materials known as organic synthetic metals do display both conductivity
and superconductivity. In the early 1990's, one such compound
was shown to super conduct at approximately 33 K (-240o C). Although
this is well below the temperatures achieved for ceramic oxides,
organic superconductors are considered to have great potential
for the future.
New superconducting
materials are being discovered on a regular basis, and the search
is on for room temperature superconductors, which, if discovered,
are expected to revolutionize electronics. Room temperature superconductors
(ultraconductors) are being developed for commercial applications
by Room Temperature Superconductors Inc.(ROOTS).Ultraconductors
are the result of more than 16 years of scientific research ,independent
laboratory testing and eight years of engineering development.
From an engineering perspective, ultraconductors are a fundamentally
new and enabling technology. These materials are claimed to conduct
electricity at least 100,000 times better than gold, silver or
copper.
1.2 Technical
introduction
Ultraconductors
are patented1 polymers being developed for commercial applications
by Room Temperature Superconductors Inc (ROOTS). The materials
exhibit a characteristic set of properties including conductivity
and current carrying capacity equivalent to superconductors, but
without the need for cryogenic support.
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