Multifunctional Resistive Switching in a Magnetization-Graded Ni/NiMnIn/V₂O₅ Flexible Heterostructure toward Brain-Inspired Neuromorphic Computing

Abstract

Bioinspired neuromorphic computing (NC) is attracting significant research interest due to the imitation of the human brain functioning in electronic devices. The current study describes a flexible Cu/V 2 O 5 /NiMnIn-based memory device fabricated using the direct current (DC) magnetron sputtering technique on a flexible Ni substrate. It manifests the simultaneous existence of analog and abrupt switching characteristics, making it promising for neuromorphic applications. The switching behavior is explained through the proposed analytical model. In abrupt resistive switching, the device displays reasonably high OFF/ ON resistance ratio (∼4.1 × 10 3 ), endurance (∼5000 cycles), and data retention time (∼4500 s). The tunability of the device has been investigated by studying the influence of external stimuli, such as temperature and magnetic field anisotropy, on the SET voltage. The realization of long-term potentiation (LTP) and long-term depression (LTD) synaptic functions in analog switching demonstrates the nonlinear and asymmetric features of the device. The effect of temperature on the LTP, LTD, and memory window has been thoroughly investigated. The strain generated in the NiMnIn layer during the first-order martensite transformation aids in tuning the LTP and LTD of the device. The negative and positive piezomagnetic coefficients of Ni and NiMnIn lead to magnetization-graded ferromagnetic assembly and enhance the linearity of LTP and LTD. Additionally, the memory device exhibits outstanding flexibility. The current work opens up new possibilities for upcoming neuromorphic applications.