Ultimate charge transport regimes in doping-controlled graphene laminates: phonon-assisted processes revealed by the linear magnetoresistance

Abstract

Understanding and controlling the electrical properties of solution-processed 2D materials is key to further printed electronics progress. Here we demonstrate that the thermolysis of the aromatic intercalants utilized in nanosheet exfoliation for graphene laminates opens the route to achieving high intrinsic mobility and simultaneously controlling doping type ($n$- and $p$-) and concentration over a wide range. We establish that the intra-flake mobility is high by observing a linear magnetoresistance of such solution-processed graphene laminates and using it to devolve the inter-flake tunneling and intra-layer magnetotransport. Consequently, we determine the temperature dependences of the inter- and intra-layer characteristics, which both appear to be dominated by phonon-assisted processes at temperature $T>$20 Kelvin. In particular, we identify the efficiency of phonon-assisted tunneling as the main limiting factor for electrical conductivity in graphene laminates at room temperature. We also demonstrate a thermoelectric sensitivity of around 50 $\mu$V K${}^{-1}$ in a solution-processed metal-free graphene-based thermocouple.

References in corpus (14)

• Non-saturating magnetoresistance in heavily disordered semiconductors
• Linear magnetoresistance caused by mobility fluctuations in the n-doped Cd3As2
• Large nonsaturating magnetoresistance and signature of non-degenerate Dirac nodes in ZrSiS
• Charge Transport in Polycrystalline Graphene: Challenges and Opportunities
• The Quantum Twisting Microscope
• Topological Semimetal Nanostructures: From Properties to Topotronics
• Breakdown of the interlayer coherence in twisted bilayer graphene
• Magnetoresistance in two-component systems
• Giant magnetoresistance of Dirac plasma in high-mobility graphene
• Seebeck Coefficient of a Single van der Waals Junction in Twisted Bilayer Graphene
• Phonon mediated interlayer conductance in twisted graphene bilayers
• Disorder induced magnetoresistance in a two dimensional electron system
• Linear magnetoresistance in compensated graphene bilayer
• Delocalization by Disorder in Layered Systems