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 symmetry1–3. This ferromagnet has been shown to support spin-wave excitations known as magnons that can be electrically generated and detected4,5. Although long-distance magnon propagation has been demonstrated via transport measurements, important… 
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