Speaker
Description
High-field Inelastic Neutron Scattering experiments have been conducted on SrCu$_2$(BO$_3$)$_2$ up to 25.9T and we find a rich set of excitations whose energies and spectral intensities have been measured as a function of magnetic field. Using cylinder matrix-product-states calculations on the Shastry-Sutherland model with Dzyaloshinskii–Moriya interactions, we reproduce experimental spectra. Multiple unconventional spectral features such as the gradients of the one-triplet branches and the persistence of the single-triplet gap point to a condensation of spin-2 bound states, thus realizing a spin-nematic phase. The single-triplet gap reflects a direct analogy with superconductivity, suggesting that the spin-nematic phase in SrCu$_2$(BO$_3$)$_2$ is best understood as a condensate of Cooper pairs of hardcore bosons.
