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Updates
The Nobel Prize in Physics is Awarded to Three People
October 2003
The Nobel Prize is named for Alfred Nobel, a Swedish
industrialist and the inventor of dynamite. When he formed
the prize, Nobel gave instructions for the selection committee
to choose a person or persons who “shall have conferred
the greatest benefit on mankind” and “shall have
made the most important discovery or invention in the field
of physics”.
On Tuesday, October 7 the Swedish Royal
Academy of Sciences selected three such persons. The Nobel
Prize in Physics was awarded to Alexei Abrikosov, Vitaly Ginzburg,
and Anthony Leggett. They were awarded the prize for their
work in quantum physics dealing with superconductivity and
superfluidity. The three will share a cash prize of $1.3 million.
Abrikosov and Ginzburg were honored for
their work with Type-II superconductors. Leggett was recognized
for his work on the theory of superfluidity in helium-3. Both
topics deal with ideas that are not often thought of; the
quantum realm and the low-temperature realm.
At low temperatures, most metals allow
electric currents to flow without resistance. This is called
superconductivity. However, when the metals are placed in
a strong enough magnetic field, they stop being superconductors.
Type-I superconductors repel magnetic fields while Type-II
superconductors can co-exist with magnetic fields. Using a
Type-II superconductor is an advantage when dealing with something,
such as an MRI scanner, that produces a magnetic field.
Superfluids have no viscosity and,
therefore, flow freely. This phenomenon, known as superfluidity,
is only observed at temperatures near absolute zero. Superfluidity
was first observed in helium-3 in the early 1970s. Afterward,
Leggett provided an explanation of this by showing that helium-3
atoms form pairs in the same way electrons form Cooper pairs
in the BCS theory of superconductivity. Cooper pairs are electrons
that flow along attracting channels formed by the regular
structure of the positively-charged metal atoms in the material.
Activity
Research more information about superconductivity and superfluidity. Write a report about how the two concepts are related and share the information with your class.
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