Thermodynamics of free and bound magnons in graphene

  title={Thermodynamics of free and bound magnons in graphene},
  author={Andrew T. Pierce and Yonglong Xie and Seung Hwan Lee and Patrick R Forrester and Di S Wei and Kenji Watanabe and Takashi Taniguchi and Bertrand I. Halperin and Amir Yacoby},
  journal={Nature Physics},
Symmetry-broken electronic phases support neutral collective excitations. For example, monolayer graphene in the quantum Hall regime hosts a nearly ideal ferromagnetic phase at specific filling factors that spontaneously breaks the spin-rotation symmetry 1 – 3 . This ferromagnet has been shown to support spin-wave excitations known as magnons that can be electrically generated and detected 4 , 5 . Although long-distance magnon propagation has been demonstrated via transport measurements… 
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