TOPOLOGICAL QUANTUM CHARACTERISTICS OBSERVED IN THE INVESTIGATION OF THE CONDUCTIVITY IN NORMAL METALS

It is shown that the investigation of the conductivity in a single cry stal of a normal metal with a complicated Fermi surface in strong magn etic fields B can reveal integral topological characteristics which ar e determined by the topology of open-ended quasiclassical electron tra jectories. Specifically, in the case of open-ended trajectories of the general position there always exists a direction eta orthogonal to B in which the conductivity approaches zero for large B, and this direct ion lies in some integral (i.e., generated by two reciprocal-lattice v ectors) plane that remains stationary for small variations of the dire ction of B. (C) 1996 American Institute of Physics.