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arXiv · 2202.05879

Nuclear-induced dephasing and signatures of hyperfine effects in isotopically purified $^{13}$C graphene

Vincent Strenzke·Jana M. Meyer·Isabell Grandt-Ionita·Marta Prada·Hyun-Seok Kim·Martin Heilmann·Joao Marcelo J. Lopes·Lars Tiemann·Robert H. Blick
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Abstract

The hyperfine interaction between the spins of electrons and nuclei is both a blessing and a curse. It can provide a wealth of information when used as an experimental probing technique but it can also be destructive when it acts as a dephasive perturbation on the electronic system. In this work, we fabricated large scale single and multilayer isotopically-purified $^{13}$C graphene Hall bars to search for interaction effects between the nuclear magnetic moments and the electronic system. We find signatures of nuclei with a spin in the analysis of the weak localization phenomenon that shows a significant dichotomy in the scattering times of monolayer $^{12}$C and $^{13}$C graphene close the Dirac point. Microwave-induced electron spin flips were exploited to transfer momentum to the nuclei and build-up a nuclear field. The presence of a very weak nuclear field is encoded in a modulation of the electron Zeeman energy which shifts the energy for resonant absorption and reduces the $g$-factor.

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Vincent Strenzke, Jana M. Meyer, Isabell Grandt-Ionita, Marta Prada, Hyun-Seok Kim, Martin Heilmann, Joao Marcelo J. Lopes, Lars Tiemann, Robert H. Blick. 2022-02-11. Nuclear-induced dephasing and signatures of hyperfine effects in isotopically purified $^{13}$C graphene. https://doi.org/10.1103/physrevb.105.144303

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