Memristive phase switching in two-dimensional 1T′-VSe2 crystals

Charge density waves (CDWs) have received extensive attention due to their unique physical properties and potential applications in oscillators and memory devices. Transition metal dichalcogenides are typical prototypes for studying CDWs. 1T′-VSe2 films grown by molecular beam epitaxy exhibited a sudden change in resistance at about 270 K, corresponding to a critical temperature of transition from the normal phase to the CDW phase. In addition, the phase transition can be modulated by voltage and the corresponding resistance states are controllable due to local Joule heating, which could be applied to the memory device. Temperature-dependent Raman characterization showed a significant change in the Raman pattern of the 1T′-VSe2 films around 270 K, further confirming the CDW phase transition observed by electrical transport measurements. The results are important not only for understanding the microscopic physics and electrical control of CDW phases, but also probably play an important role in the future applications of these CDW materials.Charge density waves (CDWs) have received extensive attention due to their unique physical properties and potential applications in oscillators and memory devices. Transition metal dichalcogenides are typical prototypes for studying CDWs. 1T′-VSe2 films grown by molecular beam epitaxy exhibited a sudden change in resistance at about 270 K, corresponding to a critical temperature of transition from the normal phase to the CDW phase. In addition, the phase transition can be modulated by voltage and the corresponding resistance states are controllable due to local Joule heating, which could be applied to the memory device. Temperature-dependent Raman characterization showed a significant change in the Raman pattern of the 1T′-VSe2 films around 270 K, further confirming the CDW phase transition observed by electrical transport measurements. The results are important not only for understanding the microscopic physics and electrical control of CDW phases, but also probably play an important role in the future a...