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Nanotechnology + Superconductivity = Spintronics
karvind writes "Spintronics is a nanoscale technology in which information is carried not by the electron's charge, as it is in conventional microchips, but by the electron's intrinsic spin and if a reliable way can be found to control and manipulate the spins spintronic devices could offer higher data processing speeds, lower electric consumption, and many other advantages over conventional chips--including, perhaps, the ability to carry out radically new quantum computations. PhysOrg is reporting that University of Notre Dame physicist Boldizsar Janko and his colleagues have found a way to achieve this control using a magnetic semiconductor, insulator and superconducting material stack of thicknesses of order of few dozen nanometers. IBM and Stanford are also looking into spintronics."
Seems like one of the Unsolved Problems in Physics isn't exactly unsolved anymore.
Are you SURE this isn't a technology developed jointly by the press and the White House?
R(k)
Microsoft is reportedly already somewhat advanced in spintronics. A company offical reportedly said "We consider ourselves to be industry leaders when it comes to manipulation using spin."
Spintronics also represents one of the quickest transitions from lab to market, next to the transistor via GMR sensors. The hard disk read heads on the hard drives in your computer, if you bought a new disk in the past few years, already incorporates spintronic effects through GMR (Giant MagnetoResistance). Most major media storage and also electronics companies have been heavily investigating spintronics for years too, not to mention a good percentage of condensed-matter physicsists, electrical and materials-science engineers.
Spintronics is also being investigated for quantum computation because the two electron eigenstates in any direction (up / down) can make a good basis for the Zero and One states of a qubit.
But to repeat the hype, spintronics does have potential to revolutionize the electronics industry by offering a whole new degree of freedom to manipulate of the electrons. 'Classical' transistors move/detect/switch charge, adding spin to the picture allows much more flexibility, and probably higher device speeds or data densities. Eg, perhaps microprocessors can go from binary as presence/lack of charge to spintronic up/down charge. Or perhaps even base-4 using presence/absence of both spin up and spin down flavors of electrons.
Here's a semi-serious reply to your obviously tongue-in-cheek question. I'll assume by 'certain value' you mean direction, since the total spin of an electron is fixed to hbar/2.
It depends how many spins you want to align, what percentage of the total number of spins you want to align, and how accurately you want to control the direction the spins are aligned to. In a nutshell a magnet will align the spins, cooling will also align the spins (for ferromagnets and antiferromagnets). doing both will do it faster and give more control. But that adds to the cost.
At absolute zero the slightest applied magnetic field to a paramagnetic system will line the spins entirely along the direction of the applied field.
If you get a ferromagnet, you only need to cool below the curie point and then apply a field to get the spins aligned. You'll need to go to a stronger field than above to overcome the hysteresis, though.
As someone said above, a simple refrigerator magnetic will put out weak-enough fields that will allow you to align several spins, and it will have an effect on coulombs per second if you move it fast enough. Not to high degree of polarization, but enough to attract the magnet to the refrigerator, so that should answer your question.