Brillouin scattering

About: Brillouin scattering is a research topic. Over the lifetime, 11426 publications have been published within this topic receiving 178306 citations.

Elastic properties of orthorhombic KNbO3 single crystals by Brillouin scattering

Abstract: Brillouin light scattering was used to obtain elastic and piezoelectric constants for a single domain orthorhombic KNbO3 single crystal at room temperature and pressure. More than 320 measurements of longitudinal and transverse acoustic wave velocities were obtained in 160 different crystallographic directions. An inversion of these data using the literature values for the dielectric permittivity of KNbO3 resulted in the full set of elastic and piezoelectric constants for the material. It is suggested that the difference between piezoelectric constants obtained by high‐ and low‐frequency methods could be explained by the high‐frequency relaxation‐type dispersion for the dielectric constant e33 in the GHz region by analogy with BaTiO3. The directional dependence of electromechanical coupling for longitudinal and transverse acoustic waves in KNbO3 was analyzed. The obtained elastic constants were (in GPa): CE11=224(4), CE22=273(5), CE33=245(5), CE44=75(1), CE55=28.5(5), CE66=95(2), CE12=102(5), CE13=182(10)...

Streicker Bridge: a comparison between Bragg-grating long-gauge strain and temperature sensors and Brillouin scattering-based distributed strain and temperature sensors

Abstract: The Streicker Bridge at Princeton University campus has been equipped with two fiber-optic sensing technologies: discrete long-gauge sensing, based on Fiber Bragg-Gratings (FBG), and truly-distributed sensing, based on Brillouin Optical Time Domain Analysis (BOTDA). The sensors were embedded in concrete during the construction. The early age measurements, including hydration swelling and contraction, and post-tensioning of concrete were registered by both systems and placed side by side in order to compare their performances. Aside from the usual behavior, an unusual increase in strain was detected by several sensors in various cross-sections. The nature of this event is still under investigation, but preliminary study indicates early-age cracking as the cause. The comparison between the two monitoring systems shows good agreement in the areas where no unusual behavior was detected, but some discrepancies are noticed at locations where unusual behavior occurred and during the early age of concrete. These discrepancies are attributed to the spatial resolution of the distributed monitoring system and the temperature influences at early age. In this paper, general information concerning the Streicker Bridge project is given. The monitoring systems and their specifications are briefly presented. The monitoring data are analyzed and a comparison between the two systems is performed.

KrF laser with a phase-conjugate Brillouin mirror

Abstract: We report observation of phase conjugation by stimulated Brillouin scattering using KrF-laser radiation (248 nm). The backscattered signal consists of both phase-conjugate and non-phase-conjugate components, which have different temporal behavior. This phase-conjugate Brillouin mirror has been used in a double-pass KrF laser-amplifier system, and as an element in a KrF-laser resonator, to compensate for aberrations and to produce a diffraction-limited output beam.

Intense laser plasma interactions: From Janus to Nova

Abstract: An overview of intense laser plasma interactions is given. The relevant physical processes range from collisional absorption to the excitation of instabilities, such as stimulated Raman and Brillouin scattering. These processes and important consequences that include suprathermal particle generation and enhanced absorption or scattering have been examined in theory, computer simulation, and experiments. The interaction physics has been studied in experiments using electromagnetic waves with wavelengths ranging from a fraction of a micron to tens of meters. Virtually every major interaction process has now been identified in laser plasma experiments, which have grown remarkably in sophistication over the years. Various control techniques have been demonstrated, and some intensity‐wavelength regimes for efficient laser plasma coupling have been successfully identified. Indeed, current implosion experiments show excellent coupling of laser energy into thermal plasma. Future challenges include a better understanding of nonlinear levels, the competition of instabilities in large plasmas, and the beneficial effects of laser beam smoothing.

Multiwavelength all-optical clock recovery

Abstract: Multiwavelength clock recovery is especially desirable in systems that use wavelength-division-multiplexed technology. A multiwavelength clock-recovery device can greatly simplify costs by eliminating the need to have a separate regenerator for each wavelength. This letter discusses multiwavelength all-optical clock recovery using stimulated Brillouin scattering.