Quantum limit in a parallel magnetic field in layered conductors.

We show that electron wave functions in a quasi-two-dimensional conductor in a parallel magnetic field are always localized on conducting layers. In particular, wave functions and the electron spectrum in a quantum limit, where the sizes of quasiclassical electron orbits are of the order of nanoscale distances between the layers, are determined. ac infrared measurements to investigate Fermi surfaces and to test Fermi-liquid theory in quasi-two-dimensional organic and high-Tc materials in high magnetic fields, H approximately equal 10-45 T, are suggested.