The possibility of increasing diamagnetic susceptibility of pyrocarbon

The differential magnetic susceptibility and galvanometric properties of pyrocarbon are investigated by a modulation technique for magnetic fields of up to 80 kOe in the temperature range 2-300 K. A large increase in diamagnetism with a decrease in carrier concentration and a dependence of magnetic susceptibility on the magnetic field intensity have been observed. The maximum value of diamagnetic susceptibility, 0.2% of -1/4 pi, exceeds that of the pyrographite single crystal by a factor of 2 at low temperatures, and by a factor of 1.5 at room temperature; it also exceeds the values for all materials in the literature except superconductors.