Prof. Sergei Urazhdin and collaborators demonstrate the possibility to modify the thermodynamic characteristics of nanomagnets by spin current

Professor Sergei UrazhdinChemical potential of quasi-equilibrium magnon gas driven by pure spin current
Prof. Sergei Urazhdin and his collaborators at the University of Muenster, Germany, have analyzed the spectral distribution of dynamical magnetization in a nanoscale magnetic system subjected to spin current, and demonstrated that the magnetic system remains in quasi-equilibrium well described by the spin-current dependent chemical potential and effective temperature. In a room-temperature experiment, they demonstrated that appropriate spin-polarization can lower the effective temperature to 225 K (-48 C). The opposite spin-polarization increases the chemical potential until it closely approaches the lowest-energy dynamical state, demonstrating the possibility of spin current-induced room-temperature Bose-Einstein condensation of magnons – a macroscopic quantum-coherent state of the magnetization.

Article: V. E. Demidov, S. Urazhdin, B. Divinskiy, V. D. Bessonov, A. B. Rinkevich, V. V. Ustinov and S. O. Demokritov “Chemical potential of quasi-equilibrium magnon gas driven by pure spin current”, Nature Comm. 8, 1579 (2017).