Asymmetric microcavities supporting Whispering-gallery modes (WGMs) are of great significance for on-chip optical information processing. We establish asymmetric microcavities on topologically curved surfaces, where the geodesic light trajectories completely reconstruct the cavity mode features. The curvature-mediated photon-lifetime engineering enables the enhancement of the quality factors of periodic island modes by up to 200 times. Strong and weak coupling between modes of very different origins occurs when the space curvature brings them into resonance, leading to fine tailoring of the cavity photon energy and lifetime and the observation of non-Hermitian exceptional point (EP). At large space curvatures, the role of the WGMs is replaced by high-Q periodic modes protected by the high stability of island-like light trajectory. Our work demonstrates interesting physical mechanisms at the crosspoint of optical chaotic dynamics, non-Hermitian physics, and geodesic optical devices, and would initiate the novel area of geodesic microcavity photonics.

In the present work, the first (1st) and second (2nd) nearest-neighbor interaction energies are calculated by coupling the microscopic phase-field kinetic model with the calculation of phase diagrams (CALPHAD) method. The morphological evolution of the γ′ precipitate and the variation of its atomic ordering parameter for Ni–X (X = Al, Fe, Mn, Pt, or Si) alloys during aging are studied. The simulation results predict different occupation preferences for solute and solvent atoms in the γ′ phase, i.e., solute atoms are inclined to occupy the corner sites and solvent atoms tend to occupy the face sites. In order to understand the precipitation process of the γ′ phase systematically, the ordering and clustering behaviors of solute atoms are analyzed.

In recent years, the development trend of artificial intelligence is getting better and better. It has been widely used not only in the fields of big data analysis, automobile automatic driving, intelligent robot and face recognition, but also in various fields of oil and gas industry. Oil and gas production prediction is an important part of reservoir engineering, which is very important for the future production and development of strata, and can give developers some development suggestions. At present, the methods used in oil and gas production prediction are mainly traditional means such as numerical simulation and history matching. With the application of artificial intelligence in various fields of oil and gas industry, the use of machine learning models for oil and gas production prediction has become the direction of development and research. This paper summarizes the basic process and main technical means of applying machine learning model to predict oil and gas production by investigating the research of domestic and foreign scholars on artificial intelligence in oil and gas production prediction in recent years. It provides ideas and lays a foundation for future researchers to study this aspect, and also contributes to the development of smart oil fields in the future.

Single‐mode laser is of fundamental importance due to its beam quality and spectral purity. However, common lasers operate in multimode as the dimensions of most laser resonators are much larger than the operating wavelengths. Herein, the novel dual‐wavelength single‐mode lasing from a solution of self‐assembled single‐component microbelt that consists of excited‐state intramolecular proton transfer molecules is demonstrated. The large modulation of the gain regimes and the cooperative effect between gain and loss in the cavity are proven experimentally and theoretically to be effective strategies for achieving multiple‐wavelength and single‐mode operation. These results broaden optical science and provide new insight into the construction of multicolor lasers with high spectral purity for the on‐chip integrated photonic system.

In this paper, the tensile deformation behaviors of polycrystals after relaxation were studied using the phase-field-crystal (PFC) method. Here, the free energy density map characterized the 2D energy distribution of atomic configuration effectively. The application of the Read–Shockley equation distinguished high-energy grain boundary (HEGB) and low-energy grain boundary (LEGB) in large-angle grain boundary (LAGB), and they demonstrated different migration behaviors at the early and later stages. The behaviors of small-angle grain boundary (SAGB), including its migration and grains’ rotation, were also studied. Two different mechanisms of dislocation emission and absorption were explored, which demonstrates the possibility of dislocation elevating interfacial energy. The simulated results on the topological transition of grain boundaries prompted us to propose the thinking about the applications of the Neumann–Mullins law and Euler formula.