Deterministic Role of Concentration Surplus of Cation Vacancy over Anion Vacancy in Bipolar Memristive NiO.
Migration of oxygen vacancies has been proposed to play an important role in the bipolar memristive behaviors because oxygen vacancies can directly determine the local conductivity in many systems. However, a recent theoretical work demonstrated that both migration of oxygen vacancies and coexistence of cation and anion vacancies are crucial to the occurrence of bipolar memristive switching, normally observed in the small-sized NiO. So far, experimental work addressing this issue is still lacking. In this work, with conductive atomic force microscopy and combined scanning transmission electron microscopy and electron energy loss spectroscopy, we reveal that concentration surplus of Ni vacancy over O vacancy determines the bipolar memristive switching of NiO films. Our work supports the dual-defects-based model, which is of fundamental importance for understanding the memristor mechanisms beyond the well-established oxygen-vacancy-based model. Moreover, this work provides a methodology to investigate the effect of dual defects on memristive behaviors.
Department of Physics and State Key Laboratory of Low-Dimensional Quantum Physics, Tsinghua University , Beijing 100084, China.|Collaborative Innovation Center of Quantum Matter , Beijing 100084, China.
Zhong
Z
Sun
Department of Physics and State Key Laboratory of Low-Dimensional Quantum Physics, Tsinghua University , Beijing 100084, China.|Collaborative Innovation Center of Quantum Matter , Beijing 100084, China.
Yonggang
Y
Zhao
Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences , Beijing 100190, China.
Min
M
He
Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences , Beijing 100190, China.|Collaborative Innovation Center of Quantum Matter , Beijing 100084, China.
Lin
L
Gu
Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences , Beijing 100190, China.
Chao
C
Ma
Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences , Beijing 100190, China.|Collaborative Innovation Center of Quantum Matter , Beijing 100084, China.
Kuijuan
K
Jin
Department of Physics and State Key Laboratory of Low-Dimensional Quantum Physics, Tsinghua University , Beijing 100084, China.|Collaborative Innovation Center of Quantum Matter , Beijing 100084, China.
Diyang
D
Zhao
Department of Physics and State Key Laboratory of Low-Dimensional Quantum Physics, Tsinghua University , Beijing 100084, China.|Collaborative Innovation Center of Quantum Matter , Beijing 100084, China.
Nannan
N
Luo
State Key Lab of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University , Beijing 100084, China.
Qinghua
Q
Zhang
Department of Physics and State Key Laboratory of Low-Dimensional Quantum Physics, Tsinghua University , Beijing 100084, China.|Collaborative Innovation Center of Quantum Matter , Beijing 100084, China.
Na
N
Wang
Department of Physics and State Key Laboratory of Low-Dimensional Quantum Physics, Tsinghua University , Beijing 100084, China.|Collaborative Innovation Center of Quantum Matter , Beijing 100084, China.
Wenhui
W
Duan
State Key Lab of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University , Beijing 100084, China.
Ce-Wen
CW
Nan
NiO memristor; bipolar resistive switching; electron energy loss spectroscopy (EELS); ionic vacancies; scanning transmission electron microscopy (STEM)