Observation of a large hall effect in HMTSF-TCNQ below room temperature

  • J.R. Cooper
  • M. Weger
  • G. Delplanoue
  • D. Jérome
  • K. Bechgaard
V. Experimental Investigations on TTF-TCNQ and its Derivatives
Part of the Lecture Notes in Physics book series (LNP, volume 65)


Hall effect measurements are reported for three single crystals of the charge transfer salt HMTSF-TCNQ in the temperature range 1.4-200 K at ambient pressure and under hydrostatic pressures of approximately 6 Kbars. There is evidence that the high conductivity of this material at low temperatures arises from a small number of electrons with a high mobility and a low degeneracy temperature; as suggested by other experiments and a recent band-structure calculation.

The charge transfer salt HMTSF-TCNQ is exceptional in that it remains a good electrical conductor down to very low temperatures, with a conductivity parallel to the stacking axis, σhc, of at least 500 (Ω cm)−1 down to 0.05 K, and there is good agreement between the DC and microwave results. A recent investigation showed that this “metallic” behaviour was even more pronounced under hydrostatic pressures of 4 kbars or more, where d σhc/dT was often


Fermi Surface Solid State Comm Electron Pocket Transverse Magnetoresistance Charge Transfer Salt 
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Copyright information

© Akadémiai Kiadó 1977

Authors and Affiliations

  • J.R. Cooper
    • 1
  • M. Weger
    • 2
  • G. Delplanoue
    • 2
  • D. Jérome
    • 2
  • K. Bechgaard
    • 3
  1. 1.Institute of Physics of the UniversityZagrebYugoslavia
  2. 2.Laboratoire de Physique des SolidesUniversité de Paris-SudOrsayFrance
  3. 3.H.C. Oersted InstituteUniversitetsparken 5CopenhagenDenmark

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