Collective effects and instabilities of a magnon gas (A07)

• Subject Area: Experimental Condensed Matter Physics
• Term: from 2007 to 2019
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 31867626

The project addresses fundamental issues in the collective dynamics of magnon gases as model systems of interacting quasi-particles. The main goal is to study the formation of quantum macroscopic states of a magnon gas and to understand the role of multi-particle interactions, including magnon-magnon and magnon-phonon scattering processes, in the properties of these correlated states of matter in comparison with the dynamics of ultracold quantum gases and quantum spin systems investigated in the Transregio 49. This aim will be achieved through Brillouin light scattering investigations of quasi- and non-equilibrium processes in magnon gases whose density is controlled by external electromagnetic pumping and by spin-torque based magnon injection. Two main issues will be addressed, which are spatially confined and dynamically trapped magnon condensates, and coherent interactions and phase transitions in magnon gases and condensates.

• DFG Programme: CRC/Transregios
• Subproject of: TRR 49: Condensed Matter Systems with Variable Many-Body Interactions
• Applicant Institution: Goethe-Universität Frankfurt am Main
• Co-Applicant Institution: Rheinland-Pfälzische Technische Universität Kaiserslautern-Landau
• Project Heads: Professor Dr. Burkard Hillebrands; Dr. Oleksandr Serha