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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.
Particles with integer spin, such as phonons (spin 0), photons (spin 1), gravitons (spin 2) are called Bosons and obey Bose-Einstein statistics. Any number of bosons can be found in any quantum state, and at low temperatures they can condense into the ground state via Bose-Einstein Condensation.
Particles with half-integer spin, such as electrons, protons, neutrons (all spin 1/2) are called Fermions, and obey Fermi-Dirac statistics. This means interchanging two fermions in a system will cause the wavefunction of the system to acquire a factor of negative one. So if two fermions are in the same quantum state, that component of the wavefunction must be equal to it's negative - meaning zero. This is the Pauli Exclusion Principle, meaning no two fermions can ever exist in the same quantum state of a system. This effect has profound impact on physics, accounting for orbital nature of atoms, band structure of semiconductors, etc.
Anyway, back to your question about spin, another aspect of spin is that the allowable spin values must differ by integer units of hbar. So electrons, with total spin of hbar/2 are allowed two states that differ by hbar - +hbar/2 and -hbar/2. Usually the direction is chosen by an applied field, or whatever direction is chosen to measure the electron spin.
Spin is tricky because it isn't simply additive, but follows appropriate group theory. Electrons are part of SU(2) algebra, and spin interactions are weird. For example, you can simultaneously know the total spin (electrons are always hbar/2) and the spin component along one direction (for electrons this could be +hbar/2 and -hbar/2). But you cannot know the x, y, and z components simultaneously, basically because the Pauli matrices don't commute (Heisenberg uncertainty principle). So in actuality a spin-up electron really points somewhere along a cone that mostly points up, but you don't know more than that.
With two electrons, you can simultaneously know EITHER the total spin of the pair AND the total spin projected along one axis, OR you can know the projections of the two independent spins along one axis. If one electron is up and another is down, the system is in a state of 1/sqrt(2) (spin-Zero + spin-One). Also - this means that the two-electron system can exist in a Spin-1 state with the spin in one direction zero, or a Spin-0 also with the spin in one direction zero. Since the two electrons would have an integral number of spin, the system acts like a Boson. This is what allows superconductors, which are mentioned in TFA, to pair up and effectively condense.
Additionally, the spin-zero state of two electronss is very important in quantum communication, quantum teleportation, and quantum computation. This is the state with total spin zero, so no matter what direction you measure one spin, the other spin is aligned opposite.
Of course the buzzword 'spintronics' is is just 'electronics' with the word spin substituted in. The actual less-trendy synonym for spintronics is Magnetoelectronics, which is what it's usually referred to in the "real" science journals, not popular outlets like PhysOrg. magnetoelectronics.
BTW - since you mention Greek I thought a better example would be using the suffix Thon, as from Marathon, to refer to any excessivly long activity. Eg Bowl-a-thon, Dance-a-thon, Phone-a-thon, etc.