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Infrared spectroscopy of Landau levels in graphene

Z. Jiang·E. A. Henriksen·L. C. Tung·Y. -J. Wang·M. E. Schwartz·M. Y. Han·P. Kim·H. L. Stormer
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Abstract

We report infrared studies of the Landau level (LL) transitions in single layer graphene. Our specimens are density tunable and show \textit{in situ} half-integer quantum Hall plateaus. Infrared transmission is measured in magnetic fields up to B=18 T at selected LL fillings. Resonances between hole LLs and electron LLs, as well as resonances between hole and electron LLs are resolved. Their transition energies are proportional to $\sqrt{B}$ and the deduced band velocity is $\tilde{c}\approx1.1\times10^6$ m/s. The lack of precise scaling between different LL transitions indicates considerable contributions of many-particle effects to the infrared transition energies.

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Z. Jiang, E. A. Henriksen, L. C. Tung, Y. -J. Wang, M. E. Schwartz, M. Y. Han, P. Kim, H. L. Stormer. 2007-04-06. Infrared spectroscopy of Landau levels in graphene. https://doi.org/10.1103/physrevlett.98.197403

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