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We study dynamic rupture propagation on flat faults using 2D plane strain models featuring strongly rate-weakening fault friction (in a rate-and-state framework) and off-fault Drucker-Prager viscoplasticity. Plastic deformation bounds stresses near the rupture front and limits slip velocities to ∼10 m=s, a bound expected to be independent of earthquake magnitude. As originally shown for ruptures in an elastic medium (Zheng and Rice, 1998), a consequence of strongly rate-weakening friction is the existence of a critical background stress level at which self-sustaining rupture propagation, in the form of self-healing slip pulses, is just barely possible. At higher background stress levels, ruptures are cracklike. This phenomenology remains unchanged when allowing for off-fault plasticity, but the critical stress level is increased. The increase depends on the extent and magnitude of plastic deformation, which is influenced by the orientation of the initial stress field and the proximity of the initial stress state to the yield surface.

Due to the color centers induced by Na/K volatilization and Sm-doping, Sm-doped KNN transparent ceramics exhibit photochromism and reversible modulations of transmittance/luminescence intensities.

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Smart windows with adjustable transmittance via physical stimuli are eagerly desired for sorts of energy‐saving lighting systems. However, reciprocal trade‐off relationship such as high transparency and coloration/discoloration ability exists in smart windows, not conducive to optical‐electrical coupling and leap in performance. Substituting for common composites utilized in smart windows, here, single transparent ceramic‐based smart windows are reported through composition design and defect management strategies to regulate the optoelectronic performances and break off the contradictions between optical transmittance, photo‐thermochromism and electrical conductivity. By first principles calculations and precisely tuning Er3+, Ba2+, Sr2+ concentrations in non‐stoichiometric Er‐doped (K0.5Na0.5)NbO3‐(Ba, Sr)TiO3, the fabricated ceramics exhibit brilliant transparency and multi‐mode dramatical and reversible modulations of pellucidity, photoluminescence intensity, along with conductivity (over fivefold variation), enabling prominent optoelectronic information storage and modulating capacity in vivid potential applications, such as easy‐readout/erasable optical memorizers, photo‐memristors and anti‐counterfeiting displays.

Multi-mode modulations of near-infrared and visible optical behaviors in xNd-KNN translucent ceramics are induced by color center-related photochromism reactions.

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Ho3+‐doped (K0.5Na0.5)NbO3‐based transparent ceramics have been prepared via pressureless solid‐state method. The ceramics possess moderate optical transparency with the energy band gap of ~2.9 eV and submicron‐sized grains (<500 nm). The temperature‐dependent dielectric properties and ferroelectric polarization‐electric field hysteresis loops demonstrate that the ceramics own relaxor‐like characteristics. The up‐conversion photoluminescence and optical temperature sensing properties of the ceramics have been investigated. The temperature dependence of photoluminescence provides a fluorescent method to detect phase transitions, which can be expanded to other ferroelectric systems. The outstanding optical temperature sensitivity (~0.0075/K at 430 K) of the ceramic is higher than many other rare‐earth‐doped ceramics or glasses. These results suggest that the Ho3+‐doped (K0.5Na0.5)NbO3‐based transparent ceramics are promising lead‐free transparent materials for multifunctional applications, especially in temperature sensing devices.