Multi-state resistive switching memory has attracted attention in the development of information technology owing to its high storage density and rapid switching.However,the degradation of their resistive properties c...Multi-state resistive switching memory has attracted attention in the development of information technology owing to its high storage density and rapid switching.However,the degradation of their resistive properties caused by charge accumulation after multiple electric-field switching severely restricts the practical application of resistive switching devices.Herein,mechanical force rather than electric field is used to prevent charge accumulation in WO_(3-δ)thin films,which is a paradigm material possessing excellent resistive switching properties and the capability to withstand significant structural distortion.The mechanical force applied through the probe tip creates an enormous inhomogeneous strain that penetrates the entire WO_(3-δ)thin film,resulting in lattice distortion and a flexoelectric field inside the WO_(3-δ)thin film,weakening the built-in electric field formed at the metal-semiconductor interface and the Schottky barrier.Eventually,excellent resistive switching is obtained with a high ON/OFF ratio(maximum>1000)and faster writing speeds.Modulating the multi-state through mechanical force can not only obtain highperformance resistive switching,but also provide a novel method to achieve multi-level memories through multi-field coupling.展开更多
Polarization switching in lead-free(K0.40Na0.60)NbO3(KNN)single crystals was studied by switching spectroscopy piezoresponse force microscopy(SS-PFM).Acquisition of multiple hysteresis loops on a closely spaced square...Polarization switching in lead-free(K0.40Na0.60)NbO3(KNN)single crystals was studied by switching spectroscopy piezoresponse force microscopy(SS-PFM).Acquisition of multiple hysteresis loops on a closely spaced square grid enables polarization switching parameters to be mapped in real space.Piezoresponse amplitude and phase hysteresis loops show collective symmetric/asymmetric characteristics,affording information regarding the switching behavior of different domains.As such,the out-of-plane polarization states of the domains,including amplitudes and phases can be determined.Our results could contribute to a further understanding of the relationships between polarization switching and polarization vectors at the nanoscale,and provide a feasible method to correlate the polarization hysteresis loops in a domain under an electric field with the polarization vector states.展开更多
基金supported by the National Key R&D Program of China(2020YFA0406202)the National Natural Science Foundation of China(22090042 and 22175018)Guangxi BaGui Scholars Special Funding(2019M660446)。
文摘Multi-state resistive switching memory has attracted attention in the development of information technology owing to its high storage density and rapid switching.However,the degradation of their resistive properties caused by charge accumulation after multiple electric-field switching severely restricts the practical application of resistive switching devices.Herein,mechanical force rather than electric field is used to prevent charge accumulation in WO_(3-δ)thin films,which is a paradigm material possessing excellent resistive switching properties and the capability to withstand significant structural distortion.The mechanical force applied through the probe tip creates an enormous inhomogeneous strain that penetrates the entire WO_(3-δ)thin film,resulting in lattice distortion and a flexoelectric field inside the WO_(3-δ)thin film,weakening the built-in electric field formed at the metal-semiconductor interface and the Schottky barrier.Eventually,excellent resistive switching is obtained with a high ON/OFF ratio(maximum>1000)and faster writing speeds.Modulating the multi-state through mechanical force can not only obtain highperformance resistive switching,but also provide a novel method to achieve multi-level memories through multi-field coupling.
基金This work was supported by Science Challenge Project(No.TZ2018003)National Natural Science Foundation of China(Grant Nos.51822206 and 5171101344).
文摘Polarization switching in lead-free(K0.40Na0.60)NbO3(KNN)single crystals was studied by switching spectroscopy piezoresponse force microscopy(SS-PFM).Acquisition of multiple hysteresis loops on a closely spaced square grid enables polarization switching parameters to be mapped in real space.Piezoresponse amplitude and phase hysteresis loops show collective symmetric/asymmetric characteristics,affording information regarding the switching behavior of different domains.As such,the out-of-plane polarization states of the domains,including amplitudes and phases can be determined.Our results could contribute to a further understanding of the relationships between polarization switching and polarization vectors at the nanoscale,and provide a feasible method to correlate the polarization hysteresis loops in a domain under an electric field with the polarization vector states.
