MAGNON BEC AT ROOM TEMPERATURE AND ITS SPATIO-TEMPORAL DYNAMICS

Recent advances in the studies of magnon gases have opened new horizons for the investigation of room-temperature macroscopic coherent states and discovery of Bose–Einstein condensation of magnons. Although the phenomenon has been discovered almost 15 years ago, a lot of important issues connected with magnon Bose–Einstein condensation remain unclear. Here I review the recent experimental achievements in investigations of this phenomenon. I show that the magnon condensate possesses high degrees of temporal and spatial coherency, the latter leading to observation of interference of two condensate. Discovery of second sound in magnon condensate is also discussed. Finally, I demonstrate a practical way to realize magnon laser, which create a freely propagating cloud of magnons.