TY - JOUR

T1 - Possible charge ordering and anomalous transport in graphene/graphene quantum dot heterostructure

AU - Roy, Rajarshi

AU - Holec, David

AU - Michal, Lukas

AU - Hemzal, Dusan

AU - Sarkar, Saikat

AU - Kumar, Gundam Sandeep

AU - Nečas, David

AU - Dhankhar, Meena

AU - Kaushik, Preeti

AU - Gómez, I. Jénnifer

AU - Zajíčková, Lenka

N1 - Publisher Copyright: © 2024 The Author(s). Published by IOP Publishing Ltd.

PY - 2024/7/3

Y1 - 2024/7/3

N2 - Observations of superconductivity and charge density waves (CDW) in graphene have been elusive thus far due to weak electron-phonon coupling (EPC) interactions. Here, we report a unique observation of anomalous transport and multiple charge ordering phases at high temperatures ( T 1 ∼ 213 K , T 2 ∼ 325 K ) in a 0D−2D van der Waals (vdW) heterostructure comprising of single layer graphene (SLG) and functionalized (amine) graphene quantum dots (GQD). The presence of functionalized GQD contributed to charge transfer with shifting of the Dirac point ∼ 0.05 eV above the Fermi level (ab initio simulations) and carrier density n ∼ − 0.3 × 10 12 cm − 2 confirming p-doping in SLG and two-fold increase in EPC interaction was achieved. Moreover, we elucidate the interplay between electron-electron and electron-phonon interactions to substantiate high temperature EPC driven charge ordering in the heterostructure through analyses of magnetotransport and weak anti-localization (WAL) framework. Our results provide impetus to investigate strongly correlated phenomena such as CDW and superconducting phase transitions in novel graphene based heterostructures.

AB - Observations of superconductivity and charge density waves (CDW) in graphene have been elusive thus far due to weak electron-phonon coupling (EPC) interactions. Here, we report a unique observation of anomalous transport and multiple charge ordering phases at high temperatures ( T 1 ∼ 213 K , T 2 ∼ 325 K ) in a 0D−2D van der Waals (vdW) heterostructure comprising of single layer graphene (SLG) and functionalized (amine) graphene quantum dots (GQD). The presence of functionalized GQD contributed to charge transfer with shifting of the Dirac point ∼ 0.05 eV above the Fermi level (ab initio simulations) and carrier density n ∼ − 0.3 × 10 12 cm − 2 confirming p-doping in SLG and two-fold increase in EPC interaction was achieved. Moreover, we elucidate the interplay between electron-electron and electron-phonon interactions to substantiate high temperature EPC driven charge ordering in the heterostructure through analyses of magnetotransport and weak anti-localization (WAL) framework. Our results provide impetus to investigate strongly correlated phenomena such as CDW and superconducting phase transitions in novel graphene based heterostructures.

KW - ab initio simulation

KW - charge ordering

KW - graphene

KW - graphene quantum dots

KW - heterostructure

KW - low temperature transport

KW - Raman spectroscopy

UR - http://www.scopus.com/inward/record.url?scp=85189349851&partnerID=8YFLogxK

U2 - 10.1088/1361-648X/ad31bf

DO - 10.1088/1361-648X/ad31bf

M3 - Article

VL - 2024

JO - Journal of physics (Condensed matter)

JF - Journal of physics (Condensed matter)

SN - 0953-8984

IS - 36

M1 - 265601

ER -