Novel PET-metal fiber-based yarn memristor as a synaptic device

PET-metal fiber spun yarn is demonstrated as a memristor device that shows switching in the resistive states in response to applied repetitive Transcranial Magnetic Stimulation (rTMS) pulses: high resistive state (HRS) to low resistive state (LRS). The phase transformation occurs in several steps due to the change in the structural phase of the yarn from the amorphous to the crystalline phase at several nodes. The structural phase change occurs due to the local joule heating at different regions where metal fibers are in closer contact with the PET fibers. The step-like change in the resistive states and the phase change of PET at multiple locations on the composite yarn mimics neuronal synaptic activity, which has a potential application in the fabrication of neuronal synaptic devices. Our results show that applying a series of longitudinal TMS pulses on the yarn decreases the resistivity non-linearly in a step-wise manner and has the potential to be used as a synaptic device with integrate-and-fire behavior similar to the biological neurons.