Bose-Einstein condensation of magnons under incoherent pumping

TL;DR

This paper demonstrates that Bose-Einstein condensation of magnons can be achieved at room temperature with incoherent pumping, with the transition point depending mainly on magnon density, and the radiated power scaling quadratically with pumping power.

Contribution

It provides experimental evidence of magnon Bose-Einstein condensation under incoherent pumping at room temperature, highlighting the independence of the transition point from pump spectrum.

Findings

Condensation achieved at room temperature with incoherent pumping

Transition point depends mainly on magnon density

Radiated power scales quadratically with pumping power

Abstract

Bose-Einstein condensation in a gas of magnons pumped by an incoherent pumping source is experimentally studied at room temperature. We demonstrate that the condensation can be achieved in a gas of bosons under conditions of incoherent pumping. Moreover, we show the critical transition point is almost independent of the frequency spectrum of the pumping source and is solely determined by the density of magnons. The electromagnetic power radiated by the magnon condensate was found to scale quadratically with the pumping power, which is in accordance with the theory of Bose-Einstein condensation in magnon gases.