Oxygen-vacancy ordering as a fatigue mechanism in perovskite ferroelectrics

Scott, J. F.; Dawber, Matthew

doi:10.1063/1.126786

Cited by 538 publications

(330 citation statements)

References 22 publications

Supporting

Mentioning

311

Contrasting

Unclassified

Order By: Relevance

“…Instead of domain vortices as in the stoichiometric sample, the domain structure exhibits random shapes in YMnO 3Àd , with one or more straight DW. At high concentration, oxygen vacancies tend to be ordered as pinning centers at DWs, forming vacancy chains and planes in ferroelectrics 15,16 such as SrTiO 3 . 17 In our sample, the concentration of oxygen vacancy reaches as high as $3%.…”

Section: Resultsmentioning

confidence: 99%

Oxygen-vacancy effect on structural, magnetic, and ferroelectric properties in multiferroic YMnO3 single crystals

Chen

Wang

et al. 2012

Journal of Applied Physics

View full text Add to dashboard Cite

We have investigated the structural, magnetic, and ferroelectric properties of magnetically frustrated multiferroic YMnO3 single crystals. The ferroelectric domain structures of YMnO3 samples were studied by piezoresponse force microscopy. Instead of domain vortex structure in stoichiometric crystals, YMnO3−δ exhibits a random domain configuration with straight domain walls. In magnetic measurements, the YMnO3−δ crystal shows typical antiferromagnetic behavior with higher Néel temperature and lower magnetization compared to the stoichiometric sample. The ordered oxygen vacancies dominate multiferroicity through tailoring the domain wall structure.

show abstract

Section: Resultsmentioning

confidence: 99%

Oxygen-vacancy effect on structural, magnetic, and ferroelectric properties in multiferroic YMnO3 single crystals

Chen

Wang

et al. 2012

Journal of Applied Physics

View full text Add to dashboard Cite

show abstract

“…This observation strongly suggests that these V O 2 þ ions Lateral BiFeO 3 cells-based ferroelectric-domain photovoltaic switch J Ho Sung et al presumably accumulated at the DWs and impede the DW motions required for domain reversal. 25,26 In perovskite oxides, it is known that mobile V O 2 þ ions tend to occupy thermodynamically preferential sites in extended crystal defects, such as DWs, grain boundaries and dislocations. [27][28][29][30][31][32][33][34] Often, these vacancies modify local cation valences and displacements and act as wall-pinning centers.…”

Section: Resultsmentioning

confidence: 99%

Single ferroelectric-domain photovoltaic switch based on lateral BiFeO3 cells

Sung

Lee

et al. 2013

NPG Asia Mater

View full text Add to dashboard Cite

The bistability of ferroelectric polarization states serves as a basis for solid-state memory. This phenomenon can also yield an interesting photovoltaic effect in such a way that the directional photocarrier motion follows the inherent potential gradient imposed by the ferroelectric polarization vectors. Here, we demonstrate a single-domain photovoltaic switch based on lateral BiFeO 3 channels, in which such photovoltaic switching is achieved by a coherent single-domain reversal with a short electrical pulse. We then provide visual evidence for such operations with a series of spatially and spectrally resolved short-circuit photocurrent images. Specifically, we reveal that the sequential photovoltaic current images directly reflect the remanent polarization states of a single-domain channel. We also verify that, in multidomain channels, diffusive switching characteristics are determined not only by the internal polarization vector within the domain but also by oxygen vacancy accumulation at the domain walls. Keywords: ferroelectrics; multiferroics; oxide photonics; photovoltaics INTRODUCTIONHomogeneous light illumination on non-centrosymmetric crystals, such as ferroelectrics, in the intrinsic absorption range can give rise to an interesting photovoltaic effect, dubbed as the bulk photovoltaic effect. 1,2 This effect is distinct from that of typical semiconductor p-n junction photovoltaics and excitonic heterojunction photovoltaics in that the photogenerated carriers can be separated along the inherent polar directions, ensuing the unidirectional photocurrent (I ph ) and photovoltage (V ph ), associated with the spontaneous ferroelectric polarization vector (P s ). Therein, the open-circuit voltage (V oc ) is determined by the magnitude of the remanent polarization of ferroelectrics, and it can be additively as large as a few hundreds of volts, although the short-circuit current (I sc I ph at 0 V) is low due to the insulating character of the system. This phenomenon has been recently revisited with a small band-gap, BiFeO 3 (BFO) ferroelectric, from which a substantially higher photon-to-charge generation efficiency can be achieved in the visible range compared with that of other insulating ferroelectrics. [3][4][5][6][7][8] reported that diodelike rectification follows the polarization-dependent interface bandbending of BFO single-crystal slabs that are electrically switchable, that is, V oc and I sc are defined by the remanent polarization directions. In general, the spatial extent of spontaneous polarization vectors in ferroelectric crystals is typically manifested as domains (typically spanning over a few mm in size) and domain walls (DW, 1-2 nm in

show abstract

“…For example, fatigue in the switching of ferroelectric NVRAM devices has been ascribed to oxygen vacancies pinning domain walls 3 . A high concentration of oxygen vacancies is also associated with degraded dielectric and piezoelectric properties 4,5 . In other cases, oxygen vacancies can play a beneficial role.…”

Section: Introductionmentioning

confidence: 99%

First-principles study of band gap engineering via oxygen vacancy doping in perovskiteABB′O3solid solutions

Curnan

Kim

et al. 2011

Phys. Rev. B

View full text Add to dashboard Cite

Oxygen vacancies in perovskite oxide solid solutions are fundamentally interesting and technologically important. However, experimental characterization of the vacancy locations and their impact on electronic structure is challenging. We have carried out first-principles calculations on two Zr-modified solid solutions, Pb(Zn 1/3 Nb 2/3 )O3 and Pb(Mg 1/3 Nb 2/3 )O3, in which vacancies are present. We find that the vacancies are more likely to reside between low-valent cation-cation pairs than high-valent cation-cation pairs. Based on the analysis of our results, we formulate guidelines that can be used to predict the location of oxygen vacancies in perovskite solid solutions. Our results show that vacancies can have a significant impact on both the conduction and valence band energies, in some cases lowering the band gap by ≈0.5 eV. The effects of vacancies on the electronic band structure can be understood within the framework of crystal field theory.

show abstract

Oxygen-vacancy ordering as a fatigue mechanism in perovskite ferroelectrics

Abstract: We present a paradigm for fatigue in ferroelectric perovskite oxides: That of a structural phase transition in which oxygen vacancies order into two-dimensional planar arrays capable of pinning domain wall motion.

Cited by 538 publications

References 22 publications

Oxygen-vacancy effect on structural, magnetic, and ferroelectric properties in multiferroic YMnO3 single crystals

Oxygen-vacancy effect on structural, magnetic, and ferroelectric properties in multiferroic YMnO3 single crystals

Single ferroelectric-domain photovoltaic switch based on lateral BiFeO3 cells

First-principles study of band gap engineering via oxygen vacancy doping in perovskiteABB′O3solid solutions

Contact Info

Product

Resources

About