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تسجيل مستخدم جديدSwitchable domains in point contacts based on transition metal tellurides
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We report resistive switching in voltage biased point contacts (PCs) based on series of van der Waals transition metals tellurides (TMTs) such as MeTe2 (Me=Mo, W) and TaMeTe4 (Me= Ru, Rh, Ir). The switching occurs between a low resistive metallic-type state, which is the ground state, and a high resistive semiconducting-type state by applying certain bias voltage (<1V), while reverse switching takes place by applying voltage of opposite polarity. The origin of the effect can be formation of domain in PC core by applying a bias voltage, when a strong electric field (about 10kV/cm) modifies the crystal structure and controls its polarization. In addition to the discovery of the switching effect in PCs, we also suggest a simple method of material testing before functionalizing them, which offers a great advantage in finding suitable novel substances. The new functionality of studied TMTs arising from switchable domains in submicron hetero-structures that are promising, e.g., for non-volatile resistive random access memory (RRAM) engineering.
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