The present invention concerns electrically conductive nanocomposites. More specifically the electrical conductance of graphitic material can be improved significantly by a molecular coating that has well defined repeating structure. Even superconductivity of these materials may be possible at technologically meaningful temperatures.

Voltage-controlled, resistance-free electric current conduction in 2-dimensional electron gases (2DEG) and its technical application at temperatures (T) up to above room temperature can be achieved by electrons with energies E<(E.sub.F-k.sub.BT) (E.sub.F=Fermi energy, k=Boltzmann constant) of a completely filled conduction band of a 2DEG which are exposed to a magnetic field B.sub.z in the z-direction and an electric field E.sub.y in the y-direction, which forces all of them to move in cyclotron motion in the x-y-plane with a common drift velocity v.sub.Dx in the x-direction. The resulting electric drift current J.sub.x has no resistance, as the electrons involved can neither be accelerated in a sole electric field nor disturbed by scattering from defects, impurities or phonons, as all possible final states of these processes are occupied by other electrons in the 2DEG. Minor losses only occur due to J.sub.y currents of the normally conducting electrons of the 2DEG with energies between E=E.sub.Fk.sub.BT which are necessary for the generation of the E.sub.y field in the 2DEG.

An electronic platform comprising a substrate made of a ABO3 crystal (2) and at least one layer of a two-dimensional conducting sheet of carbon atoms (1) of a thickness between one and four atoms, characterized in that the conducting layer(s) is (are) placed on top of a face of the crystal whose orthogonal axis is at an angle up to 35 of the crystal's spontaneous polarization or c-axis. The invention achieves a sheet resistance lower than 1 /square at temperatures higher than 77K.

This disclosure relates to compounds of formula (I):

L.sub.nD.sub.m(B.sub.xB.sub.1-x).sub.r(Z.sub.tZ.sub.1-t).sub.qM.sub.pA.sub.y(I)

in which n, m, x, r, t, q, p, L, D, B, B, Z, Z, M, and A are defined in the specification. These compounds can exhibit superconductivity at a high temperature.

Operational characteristics of an extremely low resistance (ELR) film comprised of an ELR material may be improved by depositing a modifying material onto appropriate surfaces of the ELR film to create a modified ELR film. In some implementations of the invention, the ELR film may be in the form of a c-film. In some implementations of the invention, the ELR film may be in the form of an a-b film, an a-film or a b-film. The modified ELR film has improved operational characteristics over the ELR film alone or without the modifying material. Such operational characteristics may include operating in an ELR state at increased temperatures, carrying additional electrical charge, operating with improved magnetic properties, operating with improved mechanic properties or other improved operational characteristics. In some implementations of the invention, the ELR material is a mixed-valence copper-oxide perovskite, such as, but not limited to YBCO. In some implementations of the invention, the modifying material is a conductive material that bonds easily to oxygen, such as, but not limited to, chromium.

In one aspect, the disclosure relates to nanocrystal solids including a metastable high-pressure phase that is kinetically trapped at ambient conditions and a second phase that is thermodynamically stable at ambient conditions, methods of making the same, and articles including the same. In one aspect, the methods are generalizable across a wide range of materials. In another aspect, the nanocrystal solids may form superconducting or semiconducting materials useful in computing and other fields. This abstract is intended as a scanning tool for purposes of searching in the particular art and is not intended to be limiting of the present disclosure.