We report room-temperature ultraviolet stimulated emission and lasing from optically pumped high-quality ZnO nanowires. Emission due to the exciton-exciton scattering process shows apparent stimulated-emission behavior. Several sharp peaks associated with random laser action are seen under high pumping intensity. The mechanism of laser emission is attributed to coherent multiple scattering among the random-growth oriented nanowires. The characteristic cavity length is determined by the Fourier transform of the lasing spectrum.

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Self‐assembled vertical heterostructure with a high interface‐to‐volume ratio offers tremendous opportunities to realize intriguing properties and advanced modulation of functionalities. Here, a heterostructure composed of two visible‐light photocatalysts, BiFeO3 (BFO) and ε‐Fe2O3 (ε‐FO), is designed to investigate its photoelectrochemical performance. The structural characterization of the BFO‐FO heterostructures confirms the phase separation with BFO nanopillars embedded in the ε‐FO matrix. The investigation of band structure of the heterojunction suggests the assistance of photoexcited carrier separation, leading to an enhanced photoelectrochemical performance. The insights into the charge separation are further revealed by means of ultrafast dynamics and electrochemical impedance spectroscopies. This work shows a delicate design of the self‐assembled vertical heteroepitaxy by taking advantage of the intimate contact between two phases that can lead to a tunable charge interaction, providing a new configuration for the optimization of photoelectrochemical cell.

The even-even and even-odd nuclei 126 Xe-132 Xe and 131 Ba-137 Ba are shown to have a wellrealized SO 8 ⊃ SO 6 ⊃ SO 3 fermion dynamical symmetry. Their low-lying energy levels can be described by a unified analytical expression with two (three) adjustable parameters for even-odd (even-even) nuclei that is derived from the fermion dynamical symmetry model. Analytical expressions are given for wavefunctions and for E2 transition rates that agree well with data. The distinction between the FDSM and IBM SO 6 limits is discussed. The experimentally observed suppression of the the energy levels with increasing SO 5 quantum number τ can be explained as a perturbation of the pairing interaction on the SO 6 symmetry, which leads to an SO 5 Pairing effect for SO 6 nuclei.