High-Field ESR in Spin Systems with Competing Magnetic Interactions

In my talk I will present a short review of our recent high-field Electron Spin Resonance (ESR) studies of spin systems with competing magnetic interactions. This topic will cover Antiferromagnetic Resonance in the multiferroic hexagonal antiferro-magnet YMnO₃, ESR in the anisotropic triangular antiferromagnet Cs₂CuBr₄, and organic spin-1/2 chain systems [Cu(C₄H₄N₂)(NO₃)₂ and (C₆H₉N₂)CuCl₃], in which an additional frustration term originates either from interchain or next-nearest-neighbor exchange interactions. A brief introduction into the recent development of the high-field ESR program at the High Magnetic Field Laboratory in Dresden will be also given.