Experimental evidence for electron-electron interaction and spin-charge separation in graphene quantum dots

Fuente: arXiv
Gespeichert in:
Bibliographische Detailangaben
Hauptverfasser: Ren, Hui-Ying, Ren, Ya-Ning, Zheng, Qi, He, Jia-Qi, He, Lin
Format: Preprint
Veröffentlicht: 2022
Schlagworte:
Online-Zugang:
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
_version_ 1866909129936732160
author Ren, Hui-Ying
Ren, Ya-Ning
Zheng, Qi
He, Jia-Qi
He, Lin
author_facet Ren, Hui-Ying
Ren, Ya-Ning
Zheng, Qi
He, Jia-Qi
He, Lin
contents Graphene quantum dots (GQDs) can exhibit a range of spectacular phenomena such as the Klein-tunneling-induced quasibound states1-6 and Berry-phase-tuned energy spectra7-15. According to previous studies, all these interesting quantum phenomena seem to be well understood in the free electron picture1-15. However, electronic motion in the GQDs is reduced to quantized orbits by quantum confinement, which implies that the kinetic energy may be comparable to or even smaller than the Coulomb energy of the quasiparticles, possibly resulting in exotic correlated phases in the GQDs. Here we present a scanning tunneling microscopy and spectroscopy study of gate-tunable GQDs in graphene/WSe2 heterostructure devices and report for the first time the observation of electron-electron interaction and correlation-induced spin-charge separation in the GQDs. Gating allows us to precise characterize effects of the electron-electron interaction on the energy spectra of the GQDs. By measuring density of states as a function of energy and position, we explicitly uncover two density waves with different velocities in the GQDs, attributing to spin-charge separation in real space.
format Preprint
id arxiv_https___arxiv_org_abs_2211_16100
institution arXiv
publishDate 2022
record_format arxiv
spellingShingle Experimental evidence for electron-electron interaction and spin-charge separation in graphene quantum dots
Ren, Hui-Ying
Ren, Ya-Ning
Zheng, Qi
He, Jia-Qi
He, Lin
Mesoscale and Nanoscale Physics
Materials Science
Graphene quantum dots (GQDs) can exhibit a range of spectacular phenomena such as the Klein-tunneling-induced quasibound states1-6 and Berry-phase-tuned energy spectra7-15. According to previous studies, all these interesting quantum phenomena seem to be well understood in the free electron picture1-15. However, electronic motion in the GQDs is reduced to quantized orbits by quantum confinement, which implies that the kinetic energy may be comparable to or even smaller than the Coulomb energy of the quasiparticles, possibly resulting in exotic correlated phases in the GQDs. Here we present a scanning tunneling microscopy and spectroscopy study of gate-tunable GQDs in graphene/WSe2 heterostructure devices and report for the first time the observation of electron-electron interaction and correlation-induced spin-charge separation in the GQDs. Gating allows us to precise characterize effects of the electron-electron interaction on the energy spectra of the GQDs. By measuring density of states as a function of energy and position, we explicitly uncover two density waves with different velocities in the GQDs, attributing to spin-charge separation in real space.
title Experimental evidence for electron-electron interaction and spin-charge separation in graphene quantum dots
topic Mesoscale and Nanoscale Physics
Materials Science
url https://arxiv.org/abs/2211.16100