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The bulk photovoltaic effect (BPE) has drawn considerable attention due to its ability to generate photovoltages above the bandgap and reports of highly enhanced photovoltaic current when using nanoscale absorbers or nanoscale electrodes, which, however, do not lend themselves to practical, scalable implementation. Herein, it is shown that a strikingly high BPE photoresponse can be achieved in an ordinary thin-film configuration merely by tuning fundamental ferroelectric properties. Nonmonotonic dependence of the responsivity (RSC) on the ferroelectric polarization is observed and at the optimal value of the film polarization, a more than three orders of magnitude increase in the RSC from the bulk BaTiO3 value is obtained, reaching RSC close to 10−2 A W−1, the highest value reported to date for the archetypical ferroelectric BaTiO3 films. Results challenge the applicability of standard first-principles-based descriptions of BPE to thin films and the inherent weakness of BPE in ferroelectric thin films.

Antiferroelectrics, which undergo a field-induced phase transition to ferroelectric order that manifests as double-hysteresis polarization switching, exhibit great potential for dielectric, electromechanical, and electrothermal applications. Compared to their ferroelectric cousins, however, considerably fewer efforts have been made to understand and control antiferroelectrics. Here, it is demonstrated that the polarization switching behavior of an antiferroelectric can be strongly influenced and effectively regulated by point defects. In films of the canonical antiferroelectric PbZrO3 , decreasing oxygen pressure during deposition (and thus increasing adatom kinetic energy) causes unexpected "ferroelectric-like" polarization switching although the films remain in the expected antiferroelectric orthorhombic phase. This "ferroelectric-like" switching is correlated with the creation of bombardment-induced point-defect complexes which pin the antiferroelectric-ferroelectric phase boundaries, and thus effectively delay the phase transition under changing field. The effective pinning energy is extracted via temperature-dependent switching-kinetics studies. In turn, by controlling the concentration of defect complexes, the dielectric tunability of the PbZrO3 can be adjusted, including being able to convert between "positive" and "negative" tunability near zero field. This work reveals the important role and strong capability of defects to engineer antiferroelectrics for new performance and functionalities.

Domain walls separating regions of ferroelectric material with polarization oriented in different directions are crucial for applications of ferroelectrics. Rational design of ferroelectric materials requires the development of a theory describing how compositional and environmental changes affect domain walls. To model domain wall systems, a discrete microscopic Landau-Ginzburg-Devonshire (dmLGD) approach with A- and B-site cation displacements serving as order parameters is developed. Application of dmLGD to the classic BaTiO3 , KNbO3, and PbTiO3 ferroelectrics shows that A-B cation repulsion is the key interaction that couples the polarization in neighboring unit cells of the material. dmLGD decomposition of the total energy of the system into the contributions of the individual cations and their interactions enables the prediction of different properties for a wide range of ferroelectric perovskites based on the results obtained for BaTiO3 , KNbO3, and PbTiO3 only. It is found that the information necessary to estimate the structure and energy of domain-wall "defects" can be extracted from single-domain 5-atom first-principles calculations, and that "defect-like" domain walls offer a simple model system that sheds light on the relative stabilities of the ferroelectric, antiferroelectric, and paraelectric bulk phases. The dmLGD approach provides a general theoretical framework for understanding and designing ferroelectric perovskite oxides.

Makeup usage in women serves as a behavioral tactic of both intersexual attraction and intrasexual competition. However, this tactic may incur costs to men due to the artificially enhanced mate value achieved by makeup usage. Therefore, to avoid these potential costs, men may be sensitive to the makeup cues and lower their preference for women wearing makeup during mate choice, especially for men who are pursuing a long-term relationship. In the present research, we systematically tested this hypothesis by three studies. Specifically, the three studies consistently showed that adult males who were naïve in applying makeup still displayed the ability to perceive the makeup status of female faces after exposure to female faces for sufficient time (at self-paced speed) or for moderately short time (6500 ms), even when the physical attractiveness and the possibilities that the target faces had undergone cosmetic surgery were controlled. Studies further revealed that the more long-term-mating oriented male participants were able to perceive makeup cues even after exposure to female faces for only 50 ms, and they tended to lower their perceived mate value for female targets wearing makeup in long-term mating scenarios even after exposure to female faces for only 6500 ms. Taken together, these results suggest that men are sensitive to the authenticity of the physical characteristics of potential mates and they can alter their tendency of mate choices accordingly, especially for men who are pursuing a long-term relationship., Author(s): Qi Wu [sup.1] [sup.2] , Zheying Liu [sup.1] [sup.2] , Xuanchen Liu [sup.1] [sup.2] , Dongfang Chen [sup.1] [sup.2] Author Affiliations: (1) grid.411427.5, 0000 0001 0089 3695, Department of [...]

The feasibility of using white radish powder as a nitrite substitute in dry fermented pork sausages was evaluated. Four groups of sausage were prepared by using a multi-strain starter culture (VBM-60, Sacco): negative control (NC, without nitrate or nitrite), positive control (PC, with 150 mg/kg sodium nitrite), 0.5% white radish powder (R0.5), and 1% white radish powder (R1). The effects of nitrite substitution by white radish powder on the physicochemical, microbiological and sensory characteristics of dry fermented sausage during production and storage were investigated. The results showed that compared with the positive control group, the R0.5 group had higher thiobarbituric acid reactive substance (TBARS) values, better visual appearance, and lower pH, redness value, hardness and chewiness. However, no significant difference was observed in moisture content, total volatile basic nitrogen (TVB-N) value, brightness value, elasticity, cohesiveness, total bacterial count, tissue morphology, color or flavor. During storage, the R0.5 group had higher content of nitrite and lower count of lactic acid bacteria. The nitrite content in the R0.5 group was 13.03 and 16.48 mg/kg at the end of the production and storage process, respectively, which are below the national standard limit. The results indicated that 0.5% white radish powder can be used as a natural source of nitrite for the production of dry fermented sausage.

The demand for reliable memory devices capable of operating in harsh environments, such as space and vehicles, necessitates the development of high-temperature-resistant technologies. In this study, we propose a novel ferroelectric domain wall (DW) memory utilizing BiFeO3 thin films, which exhibit exceptional retention and fatigue properties at 135 °C. Achieving this performance was made possible through precise control of the oxygen vacancy density in the epitaxial thin films induced by a post-annealing procedure conducted under an appropriate oxygen pressure of 10 Pa. Initially, prototype nano-memory devices lacking post-annealing treatment demonstrated resistive switching behavior at room temperature, with a current rectification ratio of 100:1, achieved by manipulating the uncompensated DW induced by polarization switching. With the additional annealing procedure in lower oxygen pressure, the wall current magnitude of the devices increased significantly, indicating the critical role of the oxygen vacancies in modulating the DW conductivity. Moreover, the nanodevices exhibited improved polarization retention due to oxygen vacancy-mediated charge injection that can be further enhanced at the elevated temperature. The electrons trapped deeply at the artificial DW were found to stabilize the switched polarization at the expense of reduced DW conductivity, emphasizing the importance of precise control over oxygen vacancy density for achieving a balance between high DW conductivity and excellent polarization retention. [ABSTRACT FROM AUTHOR]