Spontaneous symmetry breaking is a concept of fundamental importance in many areas of physics, underpinning such diverse phenomena as ferromagnetism, superconductivity, superfluidity and the Higgs mechanism. Here we demonstrate nonreciprocity and spontaneous symmetry breaking between counter-propagating light in dielectric microresonators. The symmetry breaking corresponds to a resonance freque...

The observation of internal solitary waves (ISWs) propagating upstream along a strongly stratified bottom layer on the California shelf is reported. An increased concentration of particulates in the water column accompanies the passage of these ISW packets. The estimated local Richardson number in the bottom vicinity is around 1/4, and a vertical coefficient of eddy diffusivity of order 1022 m2...

The effect of magnetic field on torsional waves propagating in non-homogeneous viscoelastic cylindrically aeolotropic material is discussed. The elastic constants and non-homogeneity in viscoelastic medium in terms of density and elastic constant is taken. The frequency equations have been derived in the form of a determinant involving Bessel functions. Dispersion equation in each case has been...

This paper presents the preliminary results of an extensive parametric study on seismic response of two-dimensional semi-sine shaped hills to vertically propagating incident P- and SV-waves. Clear perspectives of the induced diffraction and amplification patterns are given by investigation of time-domain and frequency-domain responses. It is shown that site geometry, wave characteristics , and ...

We report on the experimental observation of waves at a liquid foam surface propagating faster than the bulk shear waves. The existence of such waves has long been debated, but the recent observation of supershear events in a geophysical context has inspired us to search for their existence in a model viscoelastic system. An optimized fast profilometry technique allows us to observe on a liquid...

Context. To study the dynamics of coronal holes and the role of waves in the acceleration of the solar wind, spectral observations were performed over polar coronal hole regions with the SUMER spectrometer on SoHO and the EIS spectrometer on Hinode. Aims. Using these observations, we aim to detect the presence of propagating waves in the corona and to study their properties. Methods. The observ...

The acoustoelastic technique for the nondestructive evaluation of stress is based on the stress-induced changes in the speed of wave propagation. In the application of acoustoelasticity. three different approaches have been adopted. For the sake of discussion. we will consider the case of a plane state of stress in an initially isotropic material. The most common technique uses shear waves prop...

Ultrasonic guided waves have been used in testing of such an elongated object as pipe. Its sensitivity and distance resolution, however, have been limited by velocity dispersion and interference of numerous propagation modes of guided waves. Trapped energy mode of vibration of thickness shear waves in a quartz plate has been widely used in frequency control and selection due to its high Q and l...

Coherent atomic motions in materials can be revealed using time-resolved X-ray and electron Bragg diffraction. Because of the size of the beam used, typically on the micron scale, the detection of nanoscale propagating waves in extended structures hitherto has not been reported. For elastic waves of complex motions, Bragg intensities contain all polarizations and they are not straightforward to...

*Correspondence: Colin J. R. Sheppard, Department of Nanophysics, Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genova, Italy e-mail: [email protected] We review Fourier methods used in the disciplines of electromagnetism and signal processing, with a view to reconciling differences in approach. In particular, Fourier methods well known in signal processing are applied to three-...