Nanodomain Engineering Research Articles

Nanodomain Engineered (K, Na)NbO3 Lead‐Free Piezoceramics: Enhanced Thermal and Cycling Reliabilities

The growing environmental concerns have been pushing the development of viable green alternatives for lead‐based piezoceramics to be one of the priorities in functional ceramic materials. A polymorphic phase transition has been utilized to enhance piezoelectric properties of lead‐free (K, Na)NbO3‐based materials, accepting the drawbacks of high temperature and cycling instabilities. Here, we present that CaZrO3‐modified (K, Na)NbO3 piezoceramics not only possess excellent performance at ambient conditions benefiting from nanodomain engineering, but also exhibit superior stability against temperature fluctuation and electrical fatigue cycling. It was found that the piezoelectric coefficient d33 is temperature independent under 4 kV/mm, which can be attributed to enhanced thermal stability of electric field engineered domain configuration; whereas the electric field induced strain exhibits excellent fatigue resistance up to 107 sesquipolar cycles. These findings render the current material an unprecedented opportunity for actuator applications demanding improved thermal and cycling reliabilities.

Domain Nanotechnology in Ferroelectric Single Crystals: Lithium Niobate and Lithium Tantalate Family

The recent achievements in domain nanotechnology in single crystals of lithium niobate and lithium tantalate family have been reviewed. The formation of nanoscale domain structures has been studied with high spatial resolution using modern experimental methods of domain visualization. Criteria of the investigated ferroelectric material selection and recent experimental achievements have been presented. The physical basis of the nanodomain engineering based on the role of nanoscale domains in formation of the domain patterns in highly non-equilibrium switching conditions has been discussed. The obtained knowledge allows us to manufacture the highly efficient periodically poled crystals for laser light frequency conversion.

Nano-domain engineering in ultrashort-period ferroelectric superlattices

Ultrashort-period PbZrO3/PbTiO3 (PTO/PZO) ferroelectric/antiferroelectric superlattices are proposed for nano-domain engineering. They behaved like single ferroelectric metamaterials with monodomain excluding a 90° domain boundary, irrespective of their total thicknesses. Further, nanosized 180° domains, as small as ∼12 nm, were achieved by applying a short pulse voltage. Such domain structures of superlattices result from the lowering of the symmetry of supercell by specific atomic stacking in superlattices, contrary to the domain structures of ferroelectric thin films developed by the strain-induced ferroelectric instability. We suggest that ferroelectric superlattices with an ultrashort-period have a clear advantage for nano-domain engineering with greatly enhanced long term stability of the domains.

ナノドメインエンジニアリングによる高性能圧電材料の創成

To develop high performance piezoelectric materials, a new method called at “nanodomain engineering” was proposed and investigated in this study. The nanodomain engineering means a method, which can produce high density nanodomain configurations by control of chemical composition, i.e., to develop an intermediate state between relaxor ferroelectrics and normal ferroelectrics. To confirm the concept, ternary system ceramics of BaTiO3-Bi(Mg1/2Ti1/2)O3-BiFeO3(BT-BMT-BF) was prepared and characterized. As the results, a formation of nanodomain configurations was confirmed by a transmission electron microscopy. Moreover, for the ceramics with the nanodomain configurations, high apparent piezoelectric constants over 500 pC/N was clearly obtained, which suggested that the concept of “nanodomain engineering” might work good.

The Nonlinear Optical Devices by Using Nano-domain Engineering

In this paper, we present our recent progress on nano-domain engineering by using the thin-sheet LiNbO3, the improved AFM technique and the electron beam irradiation method. We also demonstrate a newly developed Second Harmonic Generation device and a concept of the large capacity nano-domain memory.

Nonlinear Optical Devices by using Nano-domain Engineering

not Available.

Ferroelectric domain engineering using atomic force microscopy tip arrays in the domain breakdown regime

One of the main obstacles to ultrahigh-density scanning probe ferroelectric-based devices is the writing speed of the device when using a single tip. We report here on the application of atomic force microscopy tip arrays for nanodomain engineering in ferroelectric crystals under the domain breakdown conditions. Using a multiple-tip array, it is shown that domain writing in 200-μm-thick RbTiOPO4 crystals results in a regular one-dimensional domain grating that penetrates throughout the bulk crystal as in the case of single tip writing. This multiple tip approach paves the way to the use of scanning probe microscopy for fabrication of various nanodomain configurations for advanced optoelectronic and microelectronic devices.

Scanning Nonlinear Dielectric Microscopy : Overview -A High Resolution Tool for Observing Ferroelectric Domains and Nano-domain Engineering-

A sub-nanometer resolution Scanning Nonlinear Dielectric Microscope (SNDM) was developed for observing ferroelectric polarization. We also demonstrate that the resolution of SNDM is higher than that of a conventional piezo-response imaging. Secondly, we report new SNDM technique detecting higher nonlinear dielectric constants e 3333 and e 33333 . Higher order nonlinear dielectric imaging provides higher lateral and depth resolution. Finally, the formation of artificial small inverted domain is reported to demonstrate that SNDM system is very useful as a nano-domain engineering tool. The nano-size domain dots were successfully formed in LiTaO₃ single crystal. This means that we can obtain a very high density ferroelectric data storage with the density above 1T-bits/inch².

Scanning Nonlinear Dielectric Microscopy -A High Resolution Tool for Observing Ferroelectric Domains and Nano-domain Engineering-

A sub-nanometer resolution scanning nonlinear dielectric microscope (SNDM) was developed for the observation of ferroelectric polarization. We also demonstrate that the resolution of SNDM is higher than that of a conventional piezo-response imaging. Next, we report new SNDM technique detecting higher nonlinear dielectric constants l 3333 and l 33333 . It is expected that higher order nonlinear dielectric imaging will provide higher lateral and depth resolution. Moreover, a new type of scanning nonlinear dielectric microscope probe, called the l 311 -type probe, and a system to measure the ferroelectric polarization component parallel to the surface is developed. Finally, the formation of artificial small inverted domain is reported to demonstrate that SNDM system is very useful as a nano-domain engineering tool. The nano-size domain dots were successfully formed in LiTaO 3 single crystal. This means that we can obtain a very high density ferroelectric data storage with the density above T-bits/inch 2.