Abstract Structure and function go hand in hand. However, while a complex structure can be
relatively safely broken down into the minutest parts, and technology is now delving into …

We report observation of an inverse energy cascade in second sound acoustic turbulence in
He ii. Its onset occurs above a critical driving energy and it is accompanied by giant waves …

Nonlinear resonance analysis is a unique mathematical tool that can be used to study
resonances in relation to, but independently of, any single area of application. This is the first …

Wave turbulence (WT) occurs in systems of strongly interacting nonlinear waves and can
lead to energy flows across length and frequency scales much like those that are well known …

Rogue waves have been observed in superfluid helium. The experimental system consists
of high intensity second sound (temperature-entropy) waves within a resonant cavity. Under …

New techniques, both for generating and detecting turbulence in the helium superfluids 3 He-
B and 4 He, have recently given insight in how turbulence is started, what the dissipation …

The nonlinear dynamics of a Bose-Einstein condensate (BEC) of dipolar excitons trapped in
an external confining potential in coupled quantum wells is analyzed. It is demonstrated that …

Based on an experiment and simulations, we report that an energy cascade in surface
capillary waves can be bidirectional, that is, can simultaneously flow towards large and …

Recent work on nonlinear second sound wave propagation and acoustic turbulence in
superfluid 4 He is reviewed. Observations of direct and inverse turbulent energy cascades …

We report our experiments on the formation of second sound acoustic turbulence in
superfluid 4He. The initial growth in spectral amplitude follows power laws that steepen …