Bose-Einstein condensation of magnons in ferromagnetic thin films

作者：Kar Rakesh; Misra Anirban^*; March N H; Klein D J

来源：Phase Transitions, 2012, 85(9): 831-839.

DOI：10.1080/01411594.2012.682060

• magnon
• spin wave
• parallel pumping
• perpendicular pumping
• Bose-Einstein condensation

Experimental evidence for Bose-Einstein condensation (BEC) of magnons at room temperature in a thin film of yttrium iron garnet (YIG) excited by parallel pumping is already available and different features of the experimental results have been explained qualitatively [Nature 443, 430 (2006)]. In the present work, we explain quantitatively different aspects of this experimental observation through spin wave treatment. In the case of parallel pumping field, we have developed a formula for the time required for the formation of magnon BEC in a thin film of ferromagnetic material. This relation is found to be in good agreement with known experimental results. In a similar treatment we predict the condition for the formation of BEC of magnons in the case of perpendicular pumping.

• 出版日期2012