An epitaxial perovskite as a compact neuristor: electrical self-oscillations in TbMnO3 thin films

Developing materials that can lead to compact versions of artificial neurons (neuristors) and synapses (memristors) is the main aspiration of the nascent neuromorphic materials research field. Oscillating circuits are interesting as neuristors, as they emulate the firing of action potentials. Here we present room-temperature self-oscillating devices fabricated from epitaxial thin films of semiconducting TbMnO3. We show that the negative differential resistance regime observed in these devices, orginates from transitions across the electronic band gap of the semiconductor. The intrinsic nature of the mechanism governing the oscillations gives rise to a high degree of control and repeatability. Obtaining such properties in an epitaxial perovskite oxide opens the way towards combining self-oscillating properties with those of other piezoelectric, ferroelectric, or magnetic perovskite oxides in order to achieve hybrid neuristor-memristor functionality in compact heterostructures.

Automated summary

Developing compact versions of artificial neurons and synapses is the main goal of neuromorphic materials research. We demonstrate room-temperature self-oscillating devices made from semiconducting TbMnO3 thin films. The observed negative differential resistance in these devices originates from transitions across the electronic band gap of the semiconductor. The intrinsic nature of the oscillation mechanism allows for high control and repeatability. Obtaining such properties in an epitaxial perovskite oxide paves the way for combining self-oscillating properties with other perovskite oxides to achieve hybrid neuristor-memristor functionality in compact heterostructures.