The primary mechanism of optical memoristive devices relies on phase transitions between amorphous and crystalline states. The slow or energy‐hungry amorphous–crystalline transitions in optical phase‐change materials are detrimental to the scalability and performance of devices. Leveraging an integrated photonic platform, nonvolatile and reversible switching between two layered structures of indium selenide (In2Se3) triggered by a single nanosecond pulse is demonstrated. The high‐resolution pair distribution function reveals the detailed atomistic transition pathways between the layered structures. With interlayer “shear glide” and isosymmetric phase transition, switching between the α‐ and β‐structural states contains low re‐configurational entropy, allowing reversible switching between layered structures. Broadband refractive index contrast, optical transparency, and volumetric effect in the crystalline–crystalline phase transition are experimentally characterized in molecular‐beam‐epitaxy‐grown thin films and compared to ab initio calculations. The nonlinear resonator transmission spectra measure of incremental linear loss rate of 3.3 GHz, introduced by a 1.5 µm‐long In2Se3‐covered layer, resulted from the combinations of material absorption and scattering.

(111) silicon is widely used in current microstructures. In this study, theoretical analysis shows that different states of elastic stress may result in different eigenvalues and their respective eigenvectors of the lattice dynamics secular equation. The key point in determining the spectral character is to obtain the Raman tensor corresponding to each eigenvector whose eigenvalue can be represented by a function of the stress tensor components. As examples, the wavenumber–stress factors under some specific states of stress at typical polarization configurations were determined. Finally, a calibration experiment was performed to validate the theoretical prediction.

Nano-indentation is a destructive measurement that introduces non-uniform residual stress around each nano-indentation. Herein, the residual stress distribution around a Berkovich nano-indentation on (001)- and (111)-plane silicon was studied by micro-Raman mapping. All of the in-plane stress state components around the indentation were obtained specifically for the (001)- and (111)-plane silicon based on the expanding cavity model and the Raman-mechanical relationship. Calculating the distribution regularity of the residual stress, the effect of different crystal planes and crystal orientations was further analyzed. Finally, the stress near the vertex of the indentation was revised owing to the crack.

The unique photoelectric properties of phosphorene typically include anisotropy, hence the nondestructive and rapid identification of its crystal orientation is a key point to the investigation and application of phosphorene. Currently, the orientation identification by analyzing the Ag1 mode based on parallel-polarized Raman has severe requirements for the applicable Raman system. Therefore, it is necessary to develop a more general, convenient, and accurate method for determining the crystal orientation of phosphorene. In this paper, a method of orientation identification was proposed by using a Raman system without an analyzer and quantifying the correlation between the intensities of Ag1 and Ag2 modes with the change of the incident polarization direction. By using mechanically peeled phosphorene as specimens, Raman measurements were carried out under the Raman configurations of both parallel polarization and with no analyzer. The results show that the crystal orientation of phosphorene can be accurately identified by quantifying the Raman intensities of both Ag1 and Ag2 modes using the Raman system without an analyzer.

Silicon-based semiconductor materials, especially {001} silicon, are the main functional materials in the electronic information industry. Residual stress plays an important role in the reliability of semiconductor devices. However, the stress state is often simplified, especially when the effect of shear stress on Raman wavenumber is neglected. In this study, the relationship between the Raman wavenumber and the plane stress components of typical crystal planes is established. It is observed that only the Raman wavenumber of the {001} plane has nothing to do with plane shear stress. Finally, a calibration experiment was carried out to validate the theoretical deduction.