The Higgs Mode of Planar Coupled Spin-Ladders and its Observation in C${}_9$H${}_{18}$N${}_2$CuBr${}_4$

Tao Ying, Kai P. Schmidt, Stefan Wessel

Polarized inelastic neutron scattering experiments recently identified the amplitude (Higgs) mode in C${}_9$H${}_{18}$N${}_2$CuBr${}_4$, a two-dimensional near-quantum-critical spin-1/2 tw…