Angular dependent phenomena in low-dimensional conductors under high magnetic fields

We discuss two topics on the phenomena depending on the magnetic field orie ntation in low-dimensional conductors: (1) Angular dependence of field-indu ced spin-density-wave (FISDW) in quasi-one-dimensional (Q1D) conductors, an d (2) angular-dependent magnetoresistance oscillation (Yamaji oscillations) in quasi-two-dimensional (Q2D) conductors without coherent interlayer coup ling. The threshold fields of FISDW transition in an organic Q1D conductor (TMTSF)(2)ClO4 shows sharp decreases at Lebed's magic angles. We extend the "standard theory" of FISDW for the three-dimensional system, and try to ex plain this feature. We prepared a series of GaAs/AlGaAs superlattices with various interlayer couplings, and experimentally show that the Yamaji oscil lations appear even in the Q2D system without coherent interlayer coupling. (C) 2001 Elsevier Science B.V. All rights reserved.