Anomalous Cooling-Rate-Dependent Charge Transport in Electrolyte-Gated Rubrene Crystals

Gate-Tuned Insulator-Metal Transition in Electrolyte-Gated Transistors Based on Tellurene

Tellurene is a recently discovered 2D material with high hole mobility and air stability, rendering it a good candidate for future applications in electronics, optoelectronics, and energy devices. However, the physical properties of tellurene remain poorly understood. In this paper, we report on the fabrication and characterization of high-performance electrolyte-gated transistors (EGTs) based on solution-grown tellurene flakes <30 nm in thickness. Both Hall measurements and resistance-temperature behavior down to 2 K are recorded at multiple gate voltages, and an electronic phase diagram is generated. The results show that it is possible to cross the insulator-metal transition in tellurene EGTs by tuning gate voltage, achieving mobility up to ∼500 cm² V^-1 s^-1. In particular, a truly metallic 2D state is observed at gate-induced hole densities >1 × 10¹³ cm^-2, as confirmed by the temperature dependence of resistance and magnetoresistance measurements. Wide-range tuning of the electronic ground state of tellurene is thus achievable in EGTs, opening up new opportunities to realize electrical control of its physical properties.

Electrolyte-based ionic control of functional oxides

The use of electrolyte gating to electrically control electronic, magnetic and optical properties of materials has seen strong recent growth, driven by the potential of the many devices and applications that such control may enable. Contrary to initial expectations of a purely electrostatic response based on electron or hole doping, electrochemical mechanisms based on the motion of ions are now understood to be common, suggesting promising new electrical control concepts.