Phonons have virtually no role to play in high-temp super conductors 

http://en.wikipedia.org/wiki/High-temperature_superconductivity#Qualitative_explanation_of_the_spin-fluctuation_mechanism

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In a conventional superconductor, Cooper pairs are created as follows. When an electron moves through the system, it creates a depression in the atomic lattice through lattice vibrations known as phonons. If the depression of the lattice is strong enough, another electron can fall into the depression created by the first electronâ€"the so-called water-bed effectâ€"and a Cooper pair is formed. When this effect becomes strong enough, Cooper pairs win over the creation of holes behind the electrons, and the normal conductor turns into a superconductor through an unlimited supply of electrons by the creation of Cooper pairs.

In a high-Tc superconductor, the mechanism is extremely similar to a conventional superconductor. Except, in this case, phonons virtually play no role and their role is replaced by spin-density waves. As all conventional superconductors are strong phonon systems, all high-Tc superconductors are strong spin-density wave systems, within close vicinity of a magnetic transition to, for example, an antiferromagnet. When an electron moves in a high-Tc superconductor, its spin creates a spin-density wave around it. This spin-density wave in turn causes a nearby electron to fall into the spin depression created by the first electron (water-bed effect again). Hence, again, a Cooper pair is formed. Eventually, when the system temperature is lowered, more spin density waves and Cooper pairs are created and superconductivity begins when an unlimited supply of Cooper pairs, denoted as a phase transition, happens. Note that in high-Tc systems, as these systems are magnetic systems due to the Coulomb interaction, there is a strong Coulomb repulsion between electrons. This Coulomb repulsion prevents pairing of the Cooper pairs on the same lattice site. The pairing of the electrons occur at near-neighbor lattice sites as a result. This is the so-called d-wave pairing, where the pairing state has a node (zero) at the origin.

Quote from: khanster on February 06, 2011, 04:05:29 AM
Phonons have virtually no role to play in high-temp super conductors 

http://en.wikipedia.org/wiki/High-temperature_superconductivity#Qualitative_explanation_of_the_spin-fluctuation_mechanism

Khanster,

Here's the thing.  Some superconductors are unconventional and can't be explaind by BCS or related theories. ( http://en.wikipedia.org/wiki/Superconductor_classification#By_the_understanding_we_have_about_them )

A fully developed theory of C60 solids superconductivity is still lacking, but it has been widely accepted that strong electronic correlations and the Jahn-Teller electron-phonon coupling produce local electron-pairings that show a high transition temperature close to the insulator-metal transition. ( http://en.wikipedia.org/wiki/Fullerenes#Superconductivity )

Now, since the fullerenes have wave-particle duality properties, we can have many C₆₀ molecules, acting as one big single atom or molecule undergoing a quantum transition at the same time which magnifies the effect, and this initiates the LENR.  When an atom or many molecules acting as a single atom undergoes a quantum transition, then all of the forces, such as the electromagnetic, weak nuclear force, and strong nuclear forces all converge.  This allows the coloumb barrier to be breached and/or allows the weak nuclear force to change the flavor of the quarks in the neutrons/protons at low energies resulting in LENR.  Phonon Resonance can force a "false quantum transition".

GB

Room temperature superconductors... They need to be invented soon 

http://en.wikipedia.org/wiki/Metallic_hydrogen#Superconductivity

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SuperconductivityIn 1968, Ashcroft put forward that metallic hydrogen may be a superconductor, up to room temperature (~290 K), far higher than any other known candidate material. This stems from its extremely high speed of sound and the expected strong coupling between the conduction electrons and the lattice vibrations.[7]

Anti-gravity cars and hover-boards need to become a reality...

Quote from: khanster on February 06, 2011, 07:27:11 PM
Room temperature superconductors... They need to be invented soon 

http://en.wikipedia.org/wiki/Metallic_hydrogen#Superconductivity


Anti-gravity cars and hover-boards need to become a reality...

This is a good find!  Metallic hydrogen shouldn't be ruled out.  This is another example of an unconventional superconductor with a strong electron-phonon coupling similiar to the C₆₀ fullerenes. Metallic hydrogen is a form of degnerate matter. ( http://en.wikipedia.org/wiki/Degenerate_matter )

This needs to be researched more.  Thanks Khanster.

GB

http://www.physorg.com/news/2011-02-neutron-analysis-reveals-doors-superconductivity.html

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Neutron scattering analysis of two families of iron-based materials suggests that the magnetic interactions thought responsible for high-temperature superconductivity may lie "two doors down": The key magnetic exchange pairings occur in a next-nearest-neighbor ordering of atoms, rather than adjacent atoms.