Quantum (Nano-scale) Limit in Organic Conductors and Superconductors in a Parallel Magnetic Field

A method to describe layered conductors and superconductors under nano-scale (quantum limit (QL)) conditions, where the "sizes" of quasi-classical electron orbits in a parallel magnetic field are of the order of the distances between conducting layeres, is suggested. We argue that these very peculiar QL properties have to be observed in a number of layered organic and high-Tc conductors and superconductors in experimental magnetic fields, H > 15 - 50 T.