Abstract
Flat band electronic systems exhibit a rich landscape of correlation-driven phases, both at the charge neutrality and finite electronic density, featuring exotic electromagnetic and thermodynamic responses. Motivated by these developments, in this paper, we explicitly include the effects of the chemical potential in a holographic model featuring approximately flat bands. In particular, we explore the phase diagram of this holographic flat band system as a function of the chemical potential. We find that at low temperatures and densities, the system features a nematic phase, transitioning into the Lifshitz phase as the chemical potential or temperature increases. To further characterize the ensuing phases, we investigate the optical conductivity and find that this observable shows strong anisotropies in the nematic phase.
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Acknowledgments
I.S.L. would like to thank Samuele Giuli for insightful discussions. This work was supported by ANID/ACT210100 (R.S.-G. and V.J), the Swedish Research Council Grant No. VR 2019-04735 (V.J.), Fondecyt (Chile) Grant No. 1200399 (R.S.-G.) and No. 1230933 (V.J.), the CONICET grants PIP-2017-1109 and PUE 084 “Búsqueda de Nueva Física”, and by UNLP grants PID-X931 (I.S.L. and N.E.G.). I.S.L. also thanks ICTP and Universidad Católica de Chile for hospitality during different stages of this project. I.S.L would like to acknowledge support from the ICTP through the Associates Programme (2023- 2028). N.E.G. thanks Universidad Católica de Chile, Universidad de Concepción and Centro de Estudios Científicos for hospitality during this project.
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Grandi, N., Juričić, V., Landea, I.S. et al. Probing holographic flat bands at finite density. J. High Energ. Phys. 2024, 30 (2024). https://doi.org/10.1007/JHEP01(2024)030
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DOI: https://doi.org/10.1007/JHEP01(2024)030