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تسجيل مستخدم جديدFermi velocity renormalization in graphene probed by terahertz time-domain spectroscopy
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We demonstrate terahertz time-domain spectroscopy (THz-TDS) to be an accurate, rapid and scalable method to probe the interaction-induced Fermi velocity renormalization { u}F^* of charge carriers in graphene. This allows the quantitative extraction of all electrical parameters (DC conductivity {sigma}DC, carrier density n, and carrier mobility {mu}) of large-scale graphene films placed on arbitrary substrates via THz-TDS. Particularly relevant are substrates with low relative permittivity (< 5) such as polymeric films, where notable renormalization effects are observed even at relatively large carrier densities (> 10^12 cm-2, Fermi level > 0.1 eV). From an application point of view, the ability to rapidly and non-destructively quantify and map the electrical ({sigma}DC, n, {mu}) and electronic ({ u}F^* ) properties of large-scale graphene on generic substrates is key to utilize this material in applications such as metrology, flexible electronics as well as to monitor graphene transfers using polymers as handling layers.
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