FIELD-INDUCED PHASE-TRANSITION IN KISH GRAPHITE

Resistance and magnetic torque of single crystals of Kish graphite, wh ich were obtained by crystallization from molten steel, have been meas ured at high magnetic fields by using 30 T resistive magnets. Below 2 K, the steep decrease of the Hall resistance is observed above the fie ld-induced phase transition. The results suggest that the electron lev els rather than the hole levels are nested at high fields where only t he lowest electron and hole Landau levels are occupied. No anomalous b ehavior is seen in the magnetization around the transition field. (C) 1998 Elsevier Science B.V. All rights reserved.