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Flexible hafnia-based ferroelectric memories are arousing much interest with the ever-growing demands for nonvolatile data storage in wearable electronic devices. Here, high-quality flexible Hf0.5Zr0.5O2membranes with robust ferroelectricity were fabricated on inorganic pliable mica substrates viaan atomic layer deposition technique. The flexible Hf0.5Zr0.5O2thin membranes with a thickness of ∼8 nm exhibit a high remanent polarization of ∼16 μC/cm2, which possess very robust polarization switching endurance (>1010cycles, two orders of magnitude better than reported flexible HfO2-based films) and superior retention ability (expected >10 years). In particular, stable ferroelectric polarization as well as excellent endurance and retention performance show negligible degradations under 6 mm radius bending conditions or after 104bending cycles with a 6 mm bending radius. These results mark a crucial step in the development of flexible hafnium oxide-based ferroelectric memories for wearable electronic devices.

Room temperature electric field controlled magnetism is extremely promising for the next-generation high-performance spintronic devices. Here, based on the ferroelectric switching driven oxygen ion migration in the Ta/Co/BiFeO3/SrRuO3heterostructures, the magnetic moment, magnetic coercive field, exchange bias field, and junction resistance are reversibly manipulated by tuning the ferroelectric polarization of the BiFeO3layer. All these phenomena are consistently explained by the oxygen ion migration induced CoOx/Co redox effect, which is evidenced by the synchrotron X-ray absorption spectroscopy measurements. Interestingly, owing to the controllable ferroelectric switching dynamics of the BiFeO3thin film, the magnetic coercive field of the Co thin film can be continuously and precisely tuned by controlling the ferroelectric polarization of the BiFeO3thin film, and the manipulating speed of the voltage control of magnetism can be fast to 100 ns. This nonvolatile, stable, reversible, fast, and reproducible voltage control of magnetism shows great potential for designing low-power and high-speed spintronics.