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تسجيل مستخدم جديدTemperature behavior of graphene conductance induced by piezoelectric effect in ferroelectric substrate
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Graphene on ferroelectric structures can be promising candidates for advanced field effect transistors, modulators and electrical transducers, providing that research of their electrotransport and electromechanical performances can be lifted up from mostly empirical to prognostic theoretical level.Recently we have shown that alternating piezoelectric displacement of the ferroelectric domain surfaces can lead to the alternate stretching and separation of graphene areas at the steps between elongated and contracted domains, and the conductance of graphene channel can be increased essentially at room temperature, because electrons in the stretched section scatter on acoustic phonons.The piezoelectric mechanism of graphene conductance control requires systematic studies of the ambient condition impact on its manifestations. This theoretical work studies in details the temperature behavior of the graphene conductance changes induced by piezoelectric effect in a ferroelectric substrate with domain stripes.We revealed the possibility to control graphene conductance (that can change up to 100 times for PZT ferroelectric substrate) by tuning the ambient temperature from low values to the critical one for given gate voltage and channel length.Also we demonstrate the possibility to control graphene conductance changes up to one hundred of times by tuning the gate voltage from 0 to the critical value at a given temperature and channel length. Obtained results can be open the way towards graphene on ferroelectric applications in piezoresistive memories operating in a wide temperature range.
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