Intrinsic space charge layers and field enhancement in ferroelectric nanojunctions

Journal Article · Mon Jul 13 00:00:00 EDT 2015 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.4926329· OSTI ID:22482264

Cao, Ye; Ievlev, Anton V.; Kalinin, Sergei V.; Maksymovych, Petro ^[1]; Morozovska, Anna N. ^[2]; Chen, Long-Qing ^[3]

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1. Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)
2. Institute of Physics, National Academy of Science of Ukraine, 46, pr. Nauki, 03028 Kiev (Ukraine)
3. Department of Material Sciences and Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802 (United States)

Conducting characteristics of topological defects in ferroelectric materials, such as charged domain walls, engendered a broad interest on their scientific merit and the possibility of novel applications utilizing domain engineering. At the same time, the problem of electron transport in ferroelectrics still remains full of unanswered questions and becomes yet more relevant over the growing interest in ferroelectric semiconductors and new improper ferroelectric materials. We have employed self-consistent phase-field modeling to investigate the physical properties of a local metal-ferroelectric (Pb(Zr{sub 0.2}Ti{sub 0.8})O{sub 3}) junction in applied electric field. We revealed an up to 10-fold local enhancement of electric field realized by large polarization gradient and over-polarization effects due to inherent non-linear dielectric properties of Pb(Zr{sub 0.2}Ti{sub 0.8})O{sub 3}. The effect is independent of bias polarity and maintains its strength prior, during and after ferroelectric switching. The observed field enhancement can be considered on similar grounds as increased doping level, giving rise to reduced switching bias and threshold voltages for charge injection, electrochemical and photoelectrochemical processes.

• OSTI ID: 22482264
• Journal Information: Applied Physics Letters, Vol. 107, Issue 2; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
DEPLETION LAYER
DIELECTRIC PROPERTIES
ELECTRIC FIELDS
ELECTRIC POTENTIAL
FERROELECTRIC MATERIALS
NANOELECTRONICS
NONLINEAR PROBLEMS
POLARIZATION
SEMICONDUCTOR MATERIALS