Magnetoresistance in the SDW state of ( TMTSF ) 2 PF 6 above T * approx 4 K —Novel effect due to the Landau quantization

Magnetoresistance in the spin-density wave (SDW) state of (TMTSF)2PF6 is known to exhibit a rich variety of the angular dependencies when a magnetic field B is rotated in the b'-c*, a-b' and a-c* planes. In the presence of a magnetic field the quasiparticle spectrum in the SDW with imperfect nesting is quantized. In such a case the minimum quasiparticle energy depends both on the magnetic field strength |B| and the angle \theta between the field and the crystal direction a, b' or c*. This approach describes rather satisfactory the magnetoresistance above T*~4K.