We report on two instabilities, called viscous fountain and viscous entrainment, triggered at the interface between two liquids by the action of bulk flows driven by a laser beam. These streaming flows are due to light scattering losses in turbid liquids, and can be directed either toward or forward the interface. We experimentally and numerically investigate these interface instabilities and s...

The stability of convection rolls in a fluid heated from below is limited by secondary instabilities, including the skew-varicose and crossroll instabilities. We observe a stability boundary defined by these same instabilities in stripe patterns in a vertically oscillated granular layer. Molecular dynamics simulations show that the mechanism of the skew-varicose instability in granular patterns...

Instabilities play a central role in the physics of foams. Some that change the topology of a dry foam are indicated by the laws promulgated by Plateau in his 1873 book. Their occurrence is less clearly predictable in wet foams. Various other instabilities are related to gravitational loading and gas compressibility. We gather up many examples as a guide to future research and identify problems...

We analytically and numerically examine the stability of three-dimensional self-trapped beams with a dark spot surrounded by bright rings of varying intensity in a uniform saturable self-focusing medium. It is shown that the fundamental bound state of the family is stable to a symmetric perturbation but unstable to an asymmetric perturbation (that breaks the azimuthal symmetry of the beam, i.e....

Morphological instability, particularly dendrite formation, can cause potentially catastrophic failure in rechargeable batteries. Morphological instabilities can lower the quality of electroplated coatings, yet may also be useful in forming porous deposits. Thus, it is important to develop strategies to control these instabilities. Liquid cell electron microscopy allows us to image in real time...

Previous theoretical work has speculated about the existence of doublediffusive magnetic buoyancy instabilities of a dynamically evolving horizontal magnetic layer generated by the interaction of forced vertically sheared velocity and a background vertical magnetic field. Here we confirm numerically that if the ratio of the magnetic to thermal diffusivities is sufficiently low then such instabi...

Bunch-by-bunch feedback systems for curing coupled-bunch instabilities in the KEKB rings have been constructed. Even at a very early stage of the commissioning of the rings, strong transverse instabilities occurred in both rings which limited maximum storable currents. Stabilization of the beams with transverse feedback systems has been successful so far, enabling us to accumulate greater beam ...

New energetic particle mode instabilities of fishbone type are predicted. The considered instabilities are driven by the circulating energetic ions. They can arise in plasmas of tokamaks and spherical tori with weak magnetic shear in the wide core region and strong shear at the periphery, provided that the central safety factor is close to the ratio m/n, where m and n are the poloidal mode numb...

We have performed 2.5D and 3D simulations of conical jets driven by the rotation of an ordered, large-scale magnetic field in a stratified atmosphere. The simulations cover about three orders of magnitude in distance to capture the centrifugal acceleration as well as the evolution past the Alfvén surface. We find that the jets develop kink instabilities, the characteristics of which depend on t...

Under nonequilibrium conditions, bosonic modes can become dynamically unstable with an exponentially growing occupation. On the other hand, topological band structures give rise to symmetry protected midgap states. In this Letter, we investigate the interplay of instability and topology. Thereby, we establish a general relation between topology and instability under ac driving. We apply our fin...