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Breaking a Superfluid Harmonic Dam: Observation and Theory of Riemann Invariants and Accelerating Sonic Horizons
Shashwat Sharan1, Judith Gonzalez Sorribes2, Patrick Sprenger1
1University of California, Merced, Department of Applied Mathematics, Merced, California 95343, USA.
Abstract:
An experimental and theoretical study of sonic horizons emerging from the dam-break problem in a Bose-Einstein condensate confined in an anisotropic harmonic trap is presented. Measurements, analysis, and numerics reveal the formation of a sonic horizon that undergoes acceleration due to harmonic confinement. The superfluid is characterized using a robust measurement technique to determine Riemann invariants. Experimental observations agree with an analytical solution of the Gross-Pitaevskii equation and computations. The collision and annihilation between two sonic horizons at long times is predicted.
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