Phase and domain engineering strategy for enhancement of piezoelectricity in the lead-free BiFeO_(3)-BaTiO_(3)ceramics

Lead-free BiFeO_(3)-BaTiO_(3)ceramics attract widespread attention over the last two decades due to their high Curie temperature(TC)and excellent piezoelectric performance.Here,in the Nd-modified 0.67BiFeO_(3)-0.33BaTiO_(3)ceramics,an excellent piezoelectric constant(d33)of 325 pC/N was achieved by applying a novel poling method(AC-biasþDC-bias)with a high TC of 455℃.In addition,an ultrahigh normalized piezoelectric strain(d33*¼Smax/Emax)of 808 pm/V was obtained at the normal/typical and relaxor-ferroelectrics phase boundary simultaneously with good thermal stability(Dd33*(T)z 20%)in the temperature range of 25e125℃.The piezoelectric force microscopy results show the domain miniaturization from micro to nanoscale/polar nano-regions due to local structure heterogeneity caused by Nd doping.The mechanism for the giant piezoelectric strain is attributed to the thermal quenching,nano-domains,and reverse switching of the short-range order to the long-range order under the applied electric field.The strategic design of domain engineering and a proposed model for the high piezoelectricity is successfully supported by the phenomenological relation and Gibbs free energy profile.In this work,a new lead-free single-element modified BiFeO_(3)-BaTiO_(3)ceramics was developed by applying a synergistic approach of domain engineering and phase boundary for the high-temperature piezoelectric performance.

Modification of physical properties of Ba(Ni_(1/3)Nb_(2/3))O_(3) ceramics through ordered domain engineering

Ordered domain engineering has been further developed for modifying and improving physical prop-erties in complex perovskite ceramics. In the present work, Ba(Ni_(1/3)Nb_(2/3))O_(3) ceramic is taken as a typicalexample for ordered domain engineering, in which the sintering temperature lies above the order-disorder transition temperature. Though the well-ordered structure could not be obtained in as-sintered samples, high ordering degree could be achieved together with preferred ordered domainstructures in Ba(Ni_(1/3)Nb_(2/3))O_(3) ceramics through long-time annealing, and subsequently the physicalproperties such as electrical resistivity, thermal conductivity, dielectric strength and energy storagedensity are significantly enhanced, where the ordering degree, ordered domain structure and ordereddomain boundary play the critical rules. The present work provides an effective approach for developingcomplex perovskite dielectric ceramics with superior physical properties.

Introduction to the Special Issue on Advances in Neutrosophic and Plithogenic Sets for Engineering and Sciences:Theory,Models,and Applications

Recently,research on uncertainty modeling has been progressing rapidly,and many essential and breakthrough studies have already been done.There are various ways to handle these uncertainties,such as fuzzy and intuitionistic fuzzy sets.Although these concepts can take incomplete information in various real-world issues,they cannot address all types of uncertainty,such as indeterminate and inconsistent information.The neutrosophic theory founded by Florentin Smarandache in 1998 constitutes a further generalization of fuzzy set,intuitionistic fuzzy set,picture fuzzy set,Pythagorean fuzzy set,spherical fuzzy set,etc.Since then,this logic has been applied in various science and engineering domains.

Polarization-dependent optical engineering of ferroelectric domains

Ferroelectric domain engineering with infrared femtosecond laser pulses has been a powerful technique to achieve a spatially modulated second-order nonlinear coefficient in three dimensions.However,studies regarding the in-fluence of laser writing conditions on the light-induced ferroelectric domain inversion remain limited.Herein,an experimental study to reveal the role of laser polarization in light-induced domain inversions is discussed.The dependence of the optical threshold and maximal writing depth of inverted domains on light polarization is ex-perimentally investigated.The results are explained by considering the second-order nonlinear optical properties and birefringence-induced focus splitting in the crystal.These findings are useful in fabricating high-quality and large-scale ferroelectric domain structures for applications in optics,electronics,and quantum technologies.

Outstanding electromechanical performance in piezoelectric ceramics via synergistic effects of defect engineering and domain miniaturization

Piezoelectric ceramics with high mechanical quality factor Q_(m) and large piezoelectric coefficient d_(33) are urgently required for advanced piezoelectric applications.However,obtaining both of these prop-erties simultaneously remains a difficult challenge due to their mutually restrictive relationship.Here 0.5Pb(Ni_(1/3)Nb_(2/3))O_(3)-0.5Pb(Zr_(0.3)Ti_(0.7))O_(3) piezoceramic with tetragonal(T)-rich MPB is designed as a matrix to construct the defect engineering by doping low-valent Mn ions.The strong coupling of defect dipole and T-rich phase can effectively hinder the rotation of P_(s),restrict domain wall motion and improve Q_(m).At the same time,the substituted Mn ions will introduce local random field,destroying the long-range or-dering of ferroelectric domain and reducing domain size.The miniaturized domain structure can increase poling efficiency and inhibit the reduction of d_(33).Guided by this strategy,Q_(m) has increased by more than 10 times and d_(33) has only decreased by about 25%.The optimized electromechanical performance with Q_(m)=822,d_(33)=502 pC/N,k_(p)=0.55 and tanδ=0.0069 can be obtained in the present study.

Patterning of large area nanoscale domains in as-grown epitaxial ferroelectric PbTiO_(3)films

Effective tuning of nanoscale domain structures provides fundamental basis for controlling and engineering of various functionalities in ferroelectric materials.In this work,we demonstrate the precise patterning of nanoscopic domain structures in as-grown epitaxial PbTiO_(3)(PTO)films by merely introducing an ultrathin pre-patterned doping layer(e.g.,Fe-doped PTO).The doping layer can effectively reverse the interfacial built-in bias,consequent to a reversed initial polarization reorientation in the as-grown film,which makes it possible to transfer the nano-patterns in the doping layer into the domain structure of ferroelectric films.For instance,we have successfully fabricated large area ordered array of nanoscale cylindrical domains(downward polarization)embedded in the matrix domain with opposite polarization(upward polarization)in PTO film.These nanoscale cylinder domains also allow deterministic and reversible erasure and creation induced by biased tip scanning.The results provide an effective pathway for on-demand patterning of large area nanoscale domains in the as-grown films,which may find applications in a wide range of nanoelectronic devices.

A Method for Bio-Sequence Analysis Algorithm Development Based on the PAR Platform

The problems of biological sequence analysis have great theoretical and practical value in modern bioinformatics.Numerous solving algorithms are used for these problems,and complex similarities and differences exist among these algorithms for the same problem,causing difficulty for researchers to select the appropriate one.To address this situation,combined with the formal partition-and-recur method,component technology,domain engineering,and generic programming,the paper presents a method for the development of a family of biological sequence analysis algorithms.It designs highly trustworthy reusable domain algorithm components and further assembles them to generate specifific biological sequence analysis algorithms.The experiment of the development of a dynamic programming based LCS algorithm family shows the proposed method enables the improvement of the reliability,understandability,and development efficiency of particular algorithms.

Reuse-baseg software production technology

Software reuse is viewed as a key technology to improve software product quality and productivity. This paper discusses a series of technologies related with software reuse and software component technology: component model, which describes component's essential characteristics; component acquisition technology, of which domain engineering is the main approach; component management technology, of which component library is the kernel; application integration and composition technology, of which application engineering is the main approach; software evolution technology, of which software reengineering is the main approach, etc. This paper introduces the software development environment: JadeBird Software Production Line System, which effectively integrates the above-mentioned technologies.