High-field phase in the magnetic-field-induced electronic phase transition of graphite

The magnetoresistance of single-crystal graphite has been measured at low temperatures in pulsed high magnetic fields up to 52 T applied parallel to the c axis. Many features were found in the high-field phase after the field-induced electronic phase transition. After the sharp rise at the phase transition, the resistance shows a dramatic decrease with increasing field, indicating the reentrant character of the phase boundary. The phase transition was no longer observed at the elevated temperature of 10.8 K in a field up to 48 T. Fine structures consisting of local maxima and an inflection point were observed in the high-field phase. Although the temperature dependence of the critical field is qualitatively in accord with Yoshioka and Fukuyama's charge-density-wave model, a more detailed theory is required to explain most of the present observation.