Quantum-Like Criticality in Granular Fluids

Abstract Quantum criticality is one of the most intriguing features of quantum mechanics and is often associated with phenomena such as superfluidity, superconductivity, collective motion and density waves. This paper reports our direct observation of a quantum-like criticality in granular fluids through noise reduction and fluidity maintenance. We present a spectrogram of the nonlinear dispersion relation for granular fluids obtained via propagation of pressure waves. An order-disorder transition in granular fluids is detected by particle image velocimetry (PIV) and optical probes. The influence of this transition on the heat diffusivity in granular fluids is investigated, revealing two modes of heat diffusion above and below the critical granular temperature. Designing such granular fluids to realize quantum-like criticality behavior opens up new avenues to experimentally observe the macro-quantum state even at room temperature and can potentially be applied in industrial multiphase reactors, energy storage, and surface acoustic wave technology.