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quantum of magnetic flux



Back in October someone asked where I got the idea that magnetic flux
is quantized.
I had been under the impression that it was 'common knowledge'.

Well, maybe I am wrong, but if so, the Phys.Rev. Focus is wrong too!
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
extract from:

http://focus.aps.org/v5/st9.html

In the first, they placed the array of rings between the equivalent
of a pair of metallic plates and increased the voltage between them
until exactly one conduction electron, on average, jumped to each
ring from one of the plates, as determined by capacitance. That
voltage gave the electron's ground state energy, which increased
predictably as the team increased the magnetic
field piercing the rings. But when the field reached one quantum of
magnetic flux per ring
^^^^^^^ ^^
^^^^^^^^ ^^^^
(about 8 T), a sudden change in the ground state energies indicated
new properties of the ground state--in this case, the electron had
one unit of angular momentum in a specific direction, rather than
circulating clockwise and counterclockwise equally. In the second
measurement, the team showed that the array of rings absorbed
infrared photons with the right energies to allow transitions between
the magnetic-field-dependent quantum states they predicted.
-. .-. .-. .-. .-. .-. .-. .-. .-. .-
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Chuck Britton Education is what is left when
britton@academic.ncssm.edu you have forgotten everything
North Carolina School of Science & Math you learned in school.
(919) 286-3366 x224 Albert Einstein, 1936