J. Phys. IV France 12 (2002) Pr9-49
DOI: 10.1051/jp4:20020352

Brave new world of unconventional density waves

K. Maki¹, B. Dora², B. Korin-Hamzic³, M. Basletic⁴, A. Virosztek^{5, 6} and M.V. Kartsovnik<sup>7

1</sup>  Department of Physics and Astronomy, University of Southern California, Los Angeles, CA 90089-0484, U.S.A.
²  The Abdus Salam ICTP, P.O. Box 586, 34014 Trieste, Italy
³  Institute of Physics, P.O. Box 304, 10001 Zagreb, Croatia
⁴  Department of Physics, Faculty of Science, P.O. Box 331, 10001 Zagreb, Croatia
⁵  Department of Physics, Technical University of Budapest, 1521 Budapest, Hungary
⁶  Research Institute for Solid Sfate Physics and Optics, P.O. Box 49, 1525 Budapest, Hungary
⁷  Walther-Meissner Institute, 85748 Garching, Germany

Abstract
Recently many people discuss unconventional density wave (i.e. UCDW and USDW). Unlike in conventional density waves, the quasiparticle excitations in these systems are gapless. The appearence of these systems suggests paradigm shift from quasi ID system to quasi 2D and 3D systems. Here we limit ourselves to the angular dependent magnetoresistance (ADMR) observed in the low temperature phase (LTP) of -(BEDT-TTF) ₂KHg(SCN) ₄. Here we show that UCDW describes successfully many features of ADMR as manifestation of the Landau quantization of the quasiparticle spectrum in magnetic field. Indeed ADMR will provide a unique window to access UDW like the AF phase in URu ₂Si ₂, the pseudogap phase in high T_c cuprates and the glassy phase in organic superconductor -(ET) ₂ salts.

© EDP Sciences 2002