Transport properties of organic conductor (BEDT-TTF)2KHg(SCN)4: I. Resistance and magnetoresistance anomaly

Robust superconducting state in the low-quasiparticle-density organic metalsβ″−(BEDT−TTF)4[(Bangura1, Coldea2, Singleton3 et al. 2005Phys. Rev. B

“…The latter behavior is similar to that of quasi-two-dimensional conductors in which a density wave only partially nests the Fermi surface, leaving behind residual Fermi-surface pockets; examples include the Mo bronzes 23 and ␣-͑BEDT-TTF͒ 2 KHg͑SCN͒ 4 . 24 In such cases, the conductivity is a convolution of a metallic component, typically varying as a power law in temperature ͑due to the unnested portions of the Fermi surface͒ and an insulating component with an activated temperature dependence ͑due to the energy gap of the density-wave state͒; 9 the exact form of the resistivity will depend on which component dominates.…”

Magneto-transport properties in the density wave phase of β′′-(BEDT-TTF)2CsCd(SCN)4

“…Measurements of the Shubnikov-de Haas oscillations indicate that the electronic structure of β"-CsCd at low temperature is different from that calculated from the crystal structure at room temperature. Moreover, we found magnetic field dependence of the interlayer resistance under the magnetic field parallel to the layer also 4 based on the crystal structure at room temperature showed a large dip-like anomaly below 32 K where the hump-like anomaly started to appear. These results suggest that the hump-like anomaly is a density wave transition accompanied by nesting the one-dimensional Fermi surfaces, and that the dip-like anomaly in the magneto-resistance is ascribed to magnetic field dependence of the interlayer hopping of electrons.…”

“…This material also has a pair of large one-dimensional Fermi surfaces and a pocket, as shown in figure1. Temperature dependence of the resistance of this salt showed a hump-like anomaly between 32 K and 5 K, which is reminiscent of a charge density wave transition in α-(BEDT-TTF) 2 KHg(SCN) 4 around 8 K [4]. Measurements of the Shubnikov-de Haas oscillations indicate that the electronic structure of β"-CsCd at low temperature is different from that calculated from the crystal structure at room temperature.…”

“…Recently, we synthesized the organic conductor β"-(BEDT-TTF) 2 CsCd(SCN) 4 (abbreviated as β"-CsCd), where BEDT-TTF denotes bis(ethylene)dithio-tetrathiafulvalene. This material also has a pair of large one-dimensional Fermi surfaces and a pocket, as shown in figure1.…”

Magnetic quantum oscillations in the charge-density-wave state of the organic metals α-(BEDT-TTF)2MHg(SCN)4 with M = K and Tl

“…The compounds remain, however, metallic due to the ungapped cylindrical Fermi surface. The low-temperature state is characterized by a bunch of striking anomalies in high magnetic fields which, actually, have triggered the initial interest in these materials [22][23][24][25][26]. By now, it is clear that their behavior is largely governed by the coexistence of a narrow-gap CDW and metallic q2D carriers and, consequently, a rich phase diagram including several kinds of magnetic field-induced transitions between different CDW states, see, e.g., [27][28][29][30].…”