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Title: Temperature dependent charge transport in ferroelectrically gated graphene far from the Dirac point
Charge transport in ferroelectric (FE) gated graphene far from the Dirac point (DP) was studied in the temperature range 300 K < T < 350 K. A non-monotonic/monotonic/non-monotonic behavior in the conductivity [σ(T)] was observed as one moved away from the DP. As the gate polarization increased, additional impurity charges were compensated, which reduced charge scattering. The uncompensated charges doped graphene and σ(T) switched to a monotonic increase with increasing T. However, far from the DP, the polarization reached saturation, which resulted in still lower impurity charge scattering. The carrier concentration increased, and a non-monotonic response in σ(T) reappeared, which was attributed to phonon scattering. A theoretical model is presented that combined impurity charge and phonon scattering conduction mechanisms. The top gate polarizable FE provided a novel approach to investigate charge transport in graphene via controlled compensation of impurity charges, and in the process revealed non-monotonic behavior in σ(T) not previously seen in SiO 2 back gated graphene devices.  more » « less
Award ID(s):
1800262 1720530 2122102
NSF-PAR ID:
10390586
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
AIP Advances
Volume:
12
Issue:
7
ISSN:
2158-3226
Page Range / eLocation ID:
075008
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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