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Universal Magnetic-Field-Driven Metal-Insulator-Metal Transformations in Graphite and Bismuth

Y. Kopelevich·J. C. Medina Pantoja·R. R. da Silva·S. Moehlecke
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Abstract

Applied magnetic field induces metal - insulator and re-entrant insulator-metal transitions in both graphite and rhombohedral bismuth. The corresponding transition boundaries plotted on the magnetic field - temperature (B - T) plane nearly coincide for these semimetals and can be best described by power laws T ~ (B - B_c)^k, where B_c is a critical field at T = 0 and k = 0.45 +/- 0.05. We show that insulator-metal-insulator (I-M-I) transformations take place in the Landau level quantization regime and illustrate how the IMT in quasi-3D graphite transforms into a cascade of I-M-I transitions, related to the quantum Hall effect in quasi-2D graphite samples. We discuss the possible coupling of superconducting and excitonic correlations with the observed phenomena, as well as the signatures of quantum phase transitions associated with the M-I and I-M transformations.

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Y. Kopelevich, J. C. Medina Pantoja, R. R. da Silva, S. Moehlecke. 2006-01-03. Universal Magnetic-Field-Driven Metal-Insulator-Metal Transformations in Graphite and Bismuth. https://doi.org/10.1103/physrevb.73.165128

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