Universal dynamics of a pair condensate

Pair condensates appear in multiple branches of physics, always introducing exotic phenomena. The pair condensate in quantum magnetism is the spin nematic, whose static (quadrupolar) order is difficult to access, favoring dynamical probes. Here, we perform high-resolution neutron spectroscopy to obtain direct evidence for the presence of two spin-nematic phases induced in the triangular-lattice antiferromagnet Na2BaNi(PO4)2 by controlling the applied magnetic field. By combining precise experiments with quantitative theoretical and numerical analysis, we identify universal dynamics arising from the pair condensate. We show explicitly how the gapless Goldstone mode influences the dispersion and induces Cherenkov-like velocity-selective decay of the gapped single-quasiparticle band. These common spectral features shed new light on spin-nematic dynamics and underline the universal phenomenology shared by pair condensates across different physical systems., , # Universal dynamics of a pair condensate

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This dataset contains the raw data files and Julia scripts used to generate all figures in the manuscript \"Universal dynamics of a pair condensate\" submitted to Science. The data includes high-resolution neutron spectroscopy measurements that provide direct evidence for the presence of two spin-nematic phases induced in the triangular-lattice antiferromagnet Na₂BaNi(PO₄)₂ by controlling the applied magnetic field. These measurements, along with theoretical and numerical analyses, identify universal dynamics arising from the pair condensate, showing how the gapless Goldstone mode influences the dispersion and induces Cherenkov-like velocity-selective decay of the gapped single-quasiparticle band.

## Description of the data and file structure

The dataset is organized by figure, with separate folders for each figure in the main manuscript (Figure 2 through Figure 5) and a separate folder f...,