Enhancement of picosecond ultrasonic signals through the use of an optical cavity

Molecular Dynamics Simulation of Heat Transport in a Nanoribbon by the Thermal Wave at Different Durations of Pulse Heating

“…1) The study of nonequilibrium acoustic phonons using a variety of methods has been important in ultrasonics for development of imaging scientific tools. Starting from initial experimental and theoretical studies [2][3][4][5] on picosecond laser pulse generation and detection, propagation of picosecond laser acoustic pulses has been lately measured through transient reflectivity changes for coherent phonons in nanostructures 6,7) such as thin films 5) and vertical cavities 8) as well as in bulk materials and crystals 9) of different anisotropies at low cryogenic temperatures, and the high temporal resolution in probing propagation of single or several coherent phonons has been shown. The process of coherent phonon formation has been theoretically described by the classical and quantum equations of lattice vibration and has been primarily based on approaches to the thermoelastic effect in the absence of the diffusion process.…”

Molecular Dynamics Simulation of Coherent Phonon Generation and Its Spectral Characterization in a Nanoribbon upon Localized Pulse Heating

“…In this case, heat flow will become driven by the direct point-to-point transport of coherent phonons. Nonequilibrium acoustic phonons were studied in ultrasonics by picosecond laser pulse generation and detection 2,3) for the development of imaging scientific tools [4][5][6][7] that can be applied to nanostructures. When applied to nanoscale devices, the working conditions in a defined thermal environment assume the presence of a diffusive acoustic phonon distribution.…”