摘要
High-density ferroelectric BiFeO_(3)(BFO)nanodot arrays were developed through template-assisted tailoring of epitaxial thin films.By combining piezoresponse force microscopy(PFM)and Kelvin probe force microscopy(KPFM)imaging techniques,we found that oxygen vacancies in nanodot arrays can be transported in the presence of an electric field.Besides triple-center domains,quadruple-center domains with different vertical polarizations were also identified.This was confirmed by combining the measurements of the domain switching and polarization vector distribution.The competition between the accumulation of mobile charges,such as oxygen vacancies,on the interface and the geometric constraints of nanodots led to the formation of these topological domain states.These abnormal multi-center topological defect states pave the way for improving the storage density of ferroelectric memory devices.
基金
supported by the Natural Science Foundation of Huai’an(Grant No.HAB202150)
Natural Science Foundation of the Jiangsu Higher Education Institutions of China(Grant No.22KJD140002)
Jiangsu Students’Platform for Innovation and Entrepreneurship Training Program(Grant No.202311049095Y).
