Possible Excitonic Phase of Graphite in the Quantum Limit State

The in-plane resistivity, Hall resistivity, and magnetization of graphite were investigated in pulsed magnetic fields applied along the c-axis. The Hall resistivity approaches zero at approximately 53 T where the in-plane and out-of-plane resistivities steeply decrease. The differential magnetization also shows an anomaly at around this field with an amplitude similar to that of de Haas–van Alphen oscillations at lower fields. This transition field appears insensitive to disorder, but reduces with hole doping. These results suggest the realization of the quantum limit states above 53 T. As a plausible explanation for the observed gapped out-of-plane conduction above 53 T, the emergence of the excitonic BCS-like state in graphite is proposed.UTokyo Research掲載「量子極限状態における励起子のBCS的状態の可能性」 URI: http://www.u-tokyo.ac.jp/ja/utokyo-research/research-news/possible-excitonic-bcs-like-state-in-the-quantum-limit-state.htmlUTokyo Research "Possible excitonic BCS-like state in the quantum limit state" URI: http://www.u-tokyo.ac.jp/en/utokyo-research/research-news/possible-excitonic-bcs-like-state-in-the-quantum-limit-state.htm