Parametric amplification of matter waves in dipolar spinor Bose-Einstein condensates

TL;DR

This paper investigates how magnetic dipole-dipole interactions influence the parametric amplification of matter waves in spinor Bose-Einstein condensates, highlighting the importance of trap orientation and magnetic-field gradients.

Contribution

It demonstrates the significant role of dipolar interactions and magnetic-field gradients in the amplification process, providing insights for future experimental control.

Findings

Dipolar interactions cause a strong angular dependence in amplification dynamics.

Magnetic-field gradients significantly modify the amplification process.

Control of magnetic-field gradients is crucial for observing dipolar effects.

Abstract

Spin-changing collisions may lead under proper conditions to the parametric amplification of matter waves in spinor Bose-Einstein condensates. Magnetic dipole-dipole interactions, although typically very weak in alkaline atoms, are shown to play a very relevant role in the amplification process. We show that these interactions may lead to a strong dependence of the amplification dynamics on the angle between the trap axis and the magnetic-field orientation. We analyze as well the important role played by magnetic-field gradients, which modify also strongly the amplification process. Magnetic-field gradients must be hence carefully controlled in future experiments, in order to observe clearly the effects of the dipolar interactions in the amplification dynamics.