Prof. Ashton Bradley, Regimes of turbulence in a quantum fluid

by Prof. Ashton Bradley (University of Otago)

Monday 20 Jul 2026, 14:30 → 15:30 Europe/Rome

1/3-1 - Sala R (Dipartimento di Fisica e Astronomia - Edificio Marzolo)

Turbulence remains one of the central open problems in physics, and in quantum fluids the underlying dynamics are unusually well-characterized and controllable. In these systems, energy can flow through both wave-like excitations and topological defects, raising a basic question: how do different forms of turbulence emerge and interact in a single, coherent medium?

Motivated by experimental developments, I will discuss our recent theoretical work on driven Bose–Einstein condensates that reveals distinct regimes of steady-state turbulence as forcing is increased, spanning wave-dominated dynamics, mixed states, and dense vortex turbulence. These regimes are identified through their spectral signatures, vortex distributions, and spatial correlations, and revealing how quantum turbulence emerges and organizes across scales. In addition to confirming the weak-wave regime reported at low forcing, high-resolution spectral analysis reveals signatures of an inverse-particle cascade of acoustic energy in the strongly driven regime.