The lack of methods to experimentally detect and quantify entanglement in quantum matter impedes our ability to identify materials hosting highly entangled phases, such as quantum spin liquids. We thus investigate the feasibility of using inelastic neutron scattering (INS) to implement a model-independent measurement protocol for entanglement based on three entanglement witnesses: one-tangle, two-tangle, and quantum Fisher information (QFI). We perform high-resolution INS measurements on ${\mathrm{Cs}}_2{\mathrm{CoCl}}_4$, a close realization of the $S=1/2$ transverse-field $XXZ$ spin chain, where we can control entanglement using the magnetic field, and compare with density-matrix renormalization group calculations for validation. The three witnesses allow us to infer entanglement properties and make deductions about the quantum state in the material. We find QFI to be a particularly robust experimental probe of entanglement, whereas the one and two-tangles require more careful analysis. Our results lay the foundation for a general entanglement detection protocol for quantum spin systems.

We use inelastic neutron scattering and molecular dynamics simulation to investigate the chemical short-range order (CSRO), visible through prepeaks in the structure factors, and its relation to self-diffusion in Al–Ni melts. As a function of composition at $1795\mathrm{K}$ , Ni self-diffusion coefficients from experiment and simulation exhibit a nonlinear dependence with a pronounced increase on the Al-rich side. This comes along with a change in CSRO with increasing Al content that is related to a more dense packing of the atoms in Ni-rich Al–Ni systems.

The ability of some materials with a perfectly ordered crystal structure to mimic the heat conduction of amorphous solids is a remarkable physical property that finds applications in numerous areas of materials science, for example, in the search for more efficient thermoelectric materials that enable to directly convert heat into electricity. Here, we unveil the mechanism in which glass-like thermal conductivity emerges in tetrahedrites, a family of natural minerals extensively studied in geology and, more recently, in thermoelectricity. By investigating the lattice dynamics of two tetrahedrites of very close compositions (Cu₁₂Sb₂Te₂S₁₃ and Cu₁₀Te₄S₁₃) but with opposite glasslike and crystal thermal transport by means of powder and single-crystal inelastic neutron scattering, we demonstrate that the former originates from the peculiar chemical environment of the copper atoms giving rise to a strongly anharmonic excess of vibrational states.