Rayleigh-Taylor instability in a binary quantum fluid

Published

August 27, 2025

Author(s)

Ian Spielman, Gretchen Campbell, Stephen Eckel, Yanda Geng, Junheng Tao, Mingshu Zhao, Shouvik Mukherjee

Abstract

We experimentally investigated the Rayleigh-Taylor instability in an immiscible homogeneous Bose-Einstein condensate (BEC) in different spin states. A magnetic field gradient force pushes two BECs together and induces instability of the interface, leading to mushroom-like pattern growth. We observed both the growth rate and wave vectors as a function of the gradient, which agrees with the linearized Bogoliubov theory of interface perturbations. Then, we directly measured the dispersion relation of the stable interface modes, by parametric excitation with oscillatory magnetic gradients. We find it follows a fractional $\omega \sim k^1⁄2$ at small wavevector $k$, and $\omega \sim k^3/2}$ at large $k$, similar to the capillary-gravity waves. With a magnetization interferometry technique we observed the development of spin helix and half-quantum vortices at the interface, which marked the onset of turbulence initiated by the Rayleigh-Taylor instability.

Citation

Science Advances

Pub Type

Journals

Download Paper

Local Download

Citation

Spielman, I. , Campbell, G. , Eckel, S. , Geng, Y. , Tao, J. , Zhao, M. and Mukherjee, S. (2025), Rayleigh-Taylor instability in a binary quantum fluid, Science Advances, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=958567 (Accessed October 14, 2025)