Electronic States Below 5K in (TMTSF)2 ClO4

Abstract

At 0.1 K, in the normal state, the Hall voltage is hole like, its variation versus magnetic field is linear up to 33 kOe. The measured Hall constant, 4xl0⁻⁹ _m ³/As, does not vary between 0.1 and 7 K. In a magnetic field higher than 33 kOe, at low temperature, the magneto transport properties are very dependent on the cooling rate, even when a very low concentration of defects is expected. In standard conditions (4 hours from 30 to 4.2 K) electron like quantized Hall voltage and peaks in magnetoresistance are observed above a threshold field of 41 kOe. At the lowest cooling rate (70 hours from 30 to 4.2 K) strong hole like dips appear in the Hall voltage and the threshold field is 33 kOe. These results are understood within a model associating spin density wave phases and fully occupied Landau levels.