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arXiv · 1710.03917

Temperature-Dependent Electron-Electron Interaction in Graphene on SrTiO3

Hyejin Ryu·Jinwoong Hwang·Debin Wang·Ankit S. Disa·Jonathan Denlinger·Yuegang Zhang·Sung-Kwan Mo·Choongyu Hwang·Alessandra Lanzara
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Abstract

The electron band structure of graphene on SrTiO3 substrate has been investigated as a function of temperature. The high-resolution angle-resolved photoemission study reveals that the spectral width at Fermi energy and the Fermi velocity of graphene on SrTiO3 are comparable to those of graphene on a BN substrate. Near the charge neutrality, the energy-momentum dispersion of graphene exhibits a strong deviation from the well-known linearity, which is magnified as temperature decreases. Such modification resembles the characteristics of enhanced electron-electron interaction. Our results not only suggest that SrTiO3 can be a plausible candidate as a substrate material for applications in graphene-based electronics, but also provide a possible route towards the realization of a new type of strongly correlated electron phases in the prototypical two-dimensional system via the manipulation of temperature and a proper choice of dielectric substrates.

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Hyejin Ryu, Jinwoong Hwang, Debin Wang, Ankit S. Disa, Jonathan Denlinger, Yuegang Zhang, Sung-Kwan Mo, Choongyu Hwang, Alessandra Lanzara. 2017-10-11. Temperature-Dependent Electron-Electron Interaction in Graphene on SrTiO3. https://doi.org/10.1021/acs.nanolett.7b01650

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