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Nano-scale domain structures in multiferroic(or ferroelectric)thin films have emerged as a golden mine for novel phenomena and functionalities due to the strongly coupled lattice,charge and spin degrees of freedom [1].One of the most intriguing phenomena associated with ferroelectric domain walls is the enhanced domain wall conductance comparing with the bulk,as demonstrated in room temperature multiferroic BiFeO3 [2] and others [3,4].In rhombohedral BiFeO3,the ferroelectric polarization is along eight equivalent [111] directions,leading to three kinds of domain walls,namely,71°,109° and 180° domain walls.The previous measurements reveal the conductance at the range of~pA in the 109° and 180° domain walls,while only negligible current in the 71° domain walls [2],which has been explained based on the dramatic suppression of the potential step and band gap at the 109° and 180° domain walls.However,a recent study found that the 71° domain walls could be equally conducting as the consequence of the oxygen vacancy mediated surface tunneling [5].In this talk,we will introduce our recent results on the conductance of well-aligned 71° domain walls,and discuss the underlying mechanism of the enhanced domain wall conduction by combing the experimental results as well as the phase field simulations.We note that the reliability nature of the 71° domain wall suggests it to be a good candidate for the applications of domain wall nanoelectronics.