Many applications of thin films necessitate detailed information about their thicknesses and sound velocities. Here, we study SiO 2 /LiNbO 3 layer systems by picosecond photoacoustic metrology and measure the sound velocities of the respective layers and the film thickness of SiO 2 , which pose crucial information for the fabrication of surface-acoustic-wave filters for communication technology. Additionally, we utilize the birefringence and the accompanying change in the detection sensitivity of coherent acoustic phonons in the LiNbO 3 layer to infer information about the LiNbO 3 orientation and the layer interface.

No abstract

When a gun is fired, a number of particles and gases, which are called gunshot residue (GSR), are released. Detection of GSR particles, as an important step to solve a case, potentially indicates that a person fired a gun or somehow involved the shooting event in a close distance to discharged gun [1,2]. GSR particles consist of a combination of lead (Pb), antimony (Sb), and barium (Ba), and other elements may accompany this characteristic structure [3].Various methods are utilized in GSR analysis, which can be detected frequently on individuals' body parts, especially in the hand and around the gun. SEM/EDX is the leading method with its specificity in evaluating the morphological and analytical properties of GSR and is currently considered as the gold standard [4]. During last

No abstract

No abstract