Magnon Decay in Cs4MnSb2Cl12

Non-collinear magnetically ordered structures with a suitable dispersion allow for an unusual feature of magnon to two magnon decays. Theoretical predictions for the "120-degree" order in classical Heisenberg antiferromagnetic triangular lattice are clear, however there are several features of these decays that have so far not yet been measured. For this experiment we propose to measure the inelastic neutron scattering spectrum of single crystals of Cs4MnSb2Cl12. This material is particularly well suited for measurements of magnon decay as it has large 5/2 magnetic moments, and with moderate magnetic fields we should be able to turn on and off magnon decay.