february 4 u.s. scientists reported that they had experimentally confirmed the nano-scale superconducting coil can withstand the strong magnetic field, which for the application of superconducting technology has opened up broad prospects.
according to superconductivity theory, superconducting electron pairing in the spin form "cooper pairs" is the source of superconductivity. the so-called "cooper pairs" refers to cooper u.s. scientists found that in the crystal many free movement of electronics, there is always a result of appropriate lattice deformation and tied together to form a relatively stable electronic. but scientists have long found that, when placed in strong magnetic field in the superconductor, the electronic "cooper pairs" will be the magnetic field destroyed, the spin of electrons has also affected the superconductivity will be reduced or completely disappear. but reduce the size of superconductors, the destructive effects of the magnetic field also will be smaller, when the size of nanometer-scale superconductors, the magnetic field had been unable to undermine the "cooper pairs" of. united states university of illinois professor of physics do not zili ya jin, who confirmed this with experiments.
the researchers in the "physical review letters," published a paper that they put on a single layer of carbon nanotubes placed in a silicon wafer etched out of about 100 nm wide "ditch", the then carbon nanotubes coated with a layer of molybdenum - ge superconducting materials, the temperature dropped below the critical temperature, and to observe the nano-scale superconducting material in strong magnetic field in the response. the results showed that strong magnetic field on the impact of nano-scale superconducting materials significantly decreased. do zili ya jin, who speculated that because of super-conductor diameter is very small, only about 10 nm or so, electronic "cooper pairs" between each other, reversing the effects of magnetic field on superconductivity.
nano-scale materials, this feature will make the prospects for broader application of superconductivity. for example, the original can not transport high current superconducting coil, because the magnetic field generated by currents could weaken or destroy the superconducting coil, and if in general the incorporation of nano-scale superconducting coil of the superconducting filaments, transmitting strong current is not difficult a. in addition, the nano-scale superconducting material can also be used for magnetic resonance imaging and other fields.
do zili ya jin also said that the size of nanoscale superconducting materials can not be infinitely reduced, otherwise electronic "cooper pairs" between interfere with each other and it will weaken its superconductivity. in addition, nanoscale superconducting materials and large-sized superconducting materials is similar to the zero resistance can not be fully realized, and the materials, the smaller the size the greater the resistance of its own.