Bose-Einstein condensation in magnetic insulators

T. Giamarchi et al., Nature Physics 2006: Bose-Einstein condensation in magnetic insulators

This is a alternative way to study Bose-Einstein Condensation by means of condensation of magnon excitations.

Possible questions:

• What is BEC in general?
• Explain Fig. 1c. Why this may be considered an extension of the "independent dimer model" from the lecture?
• Which bosons order?
• Which symmertry is broken? What means XY-AFM oder?
• How to control the number of bosons?