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Antiferromagnetic-paraelectric SrMnO3 (SMO) has aroused interest because of the theoretical strong coupling between the ferroelectric and ferromagnetic states with increasing epitaxial strain. In strained SMO films, the <110> polarized state and polar distortions have been observed, although high leakage currents and air degradation have limited their experimental verification. We herein provide a conclusive demonstration of room-temperature ferroelectricity and a high dielectric constant (εr = 138.1) in tensile-strained SMO by securing samples with insulating properties and clean surfaces using selective oxygen annealing. Furthermore, a paraelectricity and low dielectric constant (εr = 6.7) in the strain-relaxed SMO film have been identified as properties of the bulk SMO, which directly proves that the ferroelectricity of the tensile-strained SMO film is due to strain-induced polarization. We believe that these findings not only provide a cornerstone for exploring the physical properties of multiferroic SMO but also inspire new directions for single-phase multiferroics. Strain engineering: oxygen locks in room-temperature ferroelectricity Thin cracks and other defects which appear in multifunctional next-generation memory materials can be suppressed through a new synthetic technique. Compounds such as strontium manganese oxide (SrMnO3) transform from insulators into electrically and magnetically active materials when fabricated into thin films that strain the crystal's natural atom-atom separations. Sanghan Lee from the Gwangju Institute of Science and Technology, South Korea, and colleagues now report the first example of room-temperature electrical activity in strained SrMnO3 thin films. The team achieved this result by capping SrMnO3 with a layer of strontium ruthenium oxide (SrRuO3), and then annealing their new material in an oxygen-rich atmosphere. The team showed that the upper capping layer maintained the strained structure while also permitting oxygen to incorporate into the lower SrMnO3 film to eliminate vacancy defects. We provide a conclusive demonstration of strain-induced room-temperature ferroelectricity in SrMnO3 thin films by securing samples with insulating properties and clean surfaces using selective oxygen annealing. These findings will not only provide a cornerstone for exploring the physical properties of multiferroic SrMnO3 but will also inspire new directions for single-phase multiferroics. [ABSTRACT FROM AUTHOR]

Although nanoscale deformation, such as nanostrain in iron-chalcogenide (FeSexTe1−x, FST) thin films, has attracted attention owing to its enhancement of general superconducting properties, including critical current density (Jc) and critical transition temperature, the development of this technique has proven to be an extremely challenging and complex process thus far. Herein, we successfully fabricated an epitaxial FST thin film with uniformly distributed nanostrain by injection of a trace amount of CeO2 inside an FST matrix using sequential pulsed laser deposition. By means of transmission electron microscopy and geometric phase analysis, we verified that the injection of a trace amount of CeO2 forms nanoscale defects, with a nanostrained region of tensile strain (εzz ≅ 0.02) along the c-axis of the FST matrix. This nanostrained FST thin film achieves a remarkable Jc of 3.5 MA/cm2 under a self-field at 6 K and a highly enhanced Jc under the entire magnetic field with respect to those of a pristine FST thin film. Superconductors: Tiny tension raises iron's limits The maximum amount of current that can be carried by iron-based superconductors can be improved by introducing deliberate defects during fabrication. Iron–selenium–tellurium thin films have recently been identified as high-temperature superconductors that may pass large quantities of current. Sanghan Lee from the Gwangju Institute of Science and Technology in South Korea and co-workers have now used lasers to deposit small amounts of cerium oxide atoms between layers of an iron–selenium–tellurium thin film. The cerium oxide particles create defects, such as selenium-deficient sites, that slightly strain the crystal lattice and let more current move through the film. Mapping these nanostrain effects with electron microscopy enabled the team to find conditions needed to enhance superconductivity while minimizing cerium oxide by-products. To enhance supercurrent of iron-chalcogenide (FST) superconductor thin films, we induced nanostrain in FST thin films. The nanostrain was generated around nanoscale defects which were formed by the inserted a trace amount of oxide artificially inside FST matrix during the growth of FST thin film using sequential pulsed laser deposition. In particular, the critical current density (Jc) of the nanostrained FST thin films was significantly improved without dominant degradation of critical transition temperature. [ABSTRACT FROM AUTHOR]

• Child deaths in front-load units mean that supplemental safety measures are needed. • A high proportion of deaths in pulsator-type washing machines was suicide (63.2%). • Suicides in pulsator-type washing machines were very rare and similar to those in bathtubs. • Some physical conditions and age increased risks of accidents in pulsator-type units. • Washing machine–related suicidal deaths have similar characteristics of bathtub suicide. We reviewed data on washing machine–related deaths between 2008 and 2020 in South Korea to analyze the case characteristics, manners of death, and causes of death. Washing machine–related deaths are very rare, and only 23 incidents were identified over the study period. Of these cases, 19 (82.6%) were related to general pulsator-type top load washing machines; the other 4 (17.4%) were related to front-load washing machines. The pulsator-type top load washing machine–related deaths occurred in people aged between 40 and 93 years (mean age, 68 years), including 9 men (47.4%) and 10 women (52.6%). The manners of death among the incidents were suicide in 12 cases (63.2%), accident in 6 cases (31.6%), and unknown in 1 case (5.3%). A Medline search of the English literature currently does not yield results for washing machine–related suicidal deaths in adults. Of the 12 suicide cases, 4 were autopsied; suicidal death was determined by postmortem investigation or based on suicide notes. Washing machine–related suicidal deaths are presumed to have characteristics similar to those of bathtub suicidal deaths. The front-load washing machine–related deaths involved boys aged between 6 and 8 years, and all cases were concluded as accidents. The cause of death was hypoxia resulting from the children being accidentally trapped inside the washing machine while playing. Greater attention to vulnerable groups, especially children and older adults, is required to reduce the rate of washing machine–related accidental or suicidal deaths. [ABSTRACT FROM AUTHOR]