Neutron scattering studies of a bond-disordered $S=1$ quantum spin liquid

We report the results of the neutron scattering studies of a bond-disordered modification of a well-known gapped $S=1$ antiferromagnetic quantum system NiCl$_{2}\cdot$4SC(NH$_{2}$)$_{2}$ (commonly referred to as DTN). The focus of the study is a zero-field spin-liquid phase of a compound with 6\% of Cl to Br substitution. Inelastic neutron time-of-flight measurements at a temperature of 60~mK were employed to map the magnetic excitation spectrum over the whole Brillouin zone with a high resolution. In addition, we have also investigated the critical properties of the field-induced phase transition in DTN specimen with various concentration of Br by means of neutron diffraction [1]. We compare these experimental results to the bulk measurements on DTN with similar levels of Cl/Br substitution and recent theoretical predictions for disordered quantum magnets.\\[4pt] [1] E. Wulf, D. H\"{u}vonen et al.; Phys. Rev. B \textbf{88}, 174418 (2013)