Observation of an Inverse Turbulent-Wave Cascade in a Driven Quantum Gas
Abstract
We observe an inverse turbulent-wave cascade, from small to large lengthscales, in a driven homogeneous 2D Bose gas. Starting with an equilibrium condensate, we drive the gas isotropically on a lengthscale much smaller than its size, and observe a nonthermal population of modes with wavelengths larger than the drive one. At long drive times, the gas exhibits a steady nonthermal momentum distribution. At lengthscales increasing from the drive one to the system size, this distribution features in turn: (i) a power-law spectrum with an exponent close to the analytical result for a particle cascade in weak-wave turbulence, and (ii) a spectrum reminiscent of a nonthermal fixed point associated with universal coarsening in an isolated 2D gas. In further experiments, based on anisotropic driving, we reveal the complete qualitative picture of how the steady-state cascade forms.
Cite
@article{arxiv.2405.01537,
title = {Observation of an Inverse Turbulent-Wave Cascade in a Driven Quantum Gas},
author = {Andrey Karailiev and Martin Gazo and Maciej Gałka and Christoph Eigen and Tanish Satoor and Zoran Hadzibabic},
journal= {arXiv preprint arXiv:2405.01537},
year = {2025}
}
Comments
Main text: 4 pages, 5 figures; Supplemental material: 1 page, 1 figure