English

Correlation-enhanced interaction of a Bose-Einstein condensate with parametric magnon pairs and virtual magnons

Quantum Gases 2023-11-01 v1

Abstract

Nonlinear interactions are crucial in science and engineering. Here, we investigate wave interactions in a highly nonlinear magnetic system driven by parametric pumping leading to Bose--Einstein condensation of spin-wave quanta -- magnons. Using Brillouin light scattering spectroscopy in yttrium-iron garnet films, we found and identified a set of nonlinear processes resulting in off-resonant spin-wave excitations -- virtual magnons. In particular, we discovered a dynamically-strong, correlation-enhanced four-wave interaction process of the magnon condensate with pairs of parametric magnons having opposite wavevectors and fully correlated phases.

Keywords

Cite

@article{arxiv.2305.06896,
  title  = {Correlation-enhanced interaction of a Bose-Einstein condensate with parametric magnon pairs and virtual magnons},
  author = {Victor S. L'vov and Anna Pomyalov and Dmytro A. Bozhko and Burkard Hillebrands and Alexander A. Serga},
  journal= {arXiv preprint arXiv:2305.06896},
  year   = {2023}
}