Magnetic manipulation by resistance switching in CeO_2/PrBa_2Cu_3O_(7-δ)/Pt heterostructure: The role of oxygen vacancies

摘要

Pronounced bipolar resistance switching with a good retention property has been observed in CeO_2/PrBa_2Cu_3O_(7-δ)/Pt heterostructure. The low resistance state and high resistance state exhibited distinguished ferromagnetic signals, as compared to the nearly non-magnetic initial state. It is found that the migration of the oxygen vacancies under electric field is mainly responsible for the electric and the magnetic changes. The modified interfacial electronic structure by the oxygen vacancy migration and the trapping/detrapping of the carriers leads to the resistance switching. The exchange interaction of the hydrogen-like orbitals formed around the singly occupied oxygen vacancies in CeO_2 is accounting for the emerged and modulated ferromagnetic signals. Temperature dependence of resistance in the low resistance state follows a variable range hopping law, further confirming that the amount of oxygen vacancies in the CeO_2 layer directly affects the hydrogen-like orbital radius, which determines the strength of the ferromagnetic coupling.