R&D: Study of Resistive Switching, Photoresponse and Magnetism Modulation in Pt/Co3O4/Nb:SrTiO3 Heterostructure

Applied Physics Letters has published an article written by Meng Zhao, Institute of Physical Science and Information Technology, Anhui University, Hefei 230601, China, Yongdan Zhu, Yuan Zhang, and Teng Zhang, School of Information Engineering, Hubei Minzu University, Enshi 445000, Hubei, People’s Republic of China.

Abstract: “Co3O4 thin films are epitaxially grown on an Nb-doped (001) SrTiO3 (NSTO) single-crystal substrate using pulsed laser deposition to form Pt/Co3O4/NSTO heterostructures. These devices display stable bipolar resistive switching (RS) with multilevel memory, good endurance, and a maximum ON/OFF ratio of up to 104. The high resistance state of the device exhibits significant photoresponse characteristics with an open-circuit voltage of 0.47 V, under the illumination of a 405 nm laser. Moreover, the saturation magnetization of the Co3O4 film shows reversible switching associated with different resistance states. The RS and related photoelectricity could be attributed to the modulation of the potential barrier via the oxygen vacancy migration coupled with electron trapping/detrapping and light illumination at the Co3O4/NSTO interface; meanwhile, the change in magnetism might be due to the redistribution of the oxygen vacancies. These results provide a promising pathway for developing multifunctional, multilevel memory devices with RS, photoresponse, and magnetism.“

This work was supported by the National Natural Science Foundation of China (Grant Nos. 11964009 and U1832209) and the Natural Science Foundation of AnHui Province (Grant No. 1908085QA20).