Emptiness formation in polytropic quantum liquids

We study large deviations in interacting quantum liquids with the polytropic equation of state P (ρ) ∼ ργ, where ρ is density and P is pressure. By solving hydrodynamic equations in imaginary time we evaluate the instanton action and calculate the emptiness formation probability (EFP), the probability that no particle resides in a macroscopic interval of a given size. Analytic solutions are found for a certain infinite sequence of rational polytropic indexes γ and the result can be analytically continued to any value of γ ≥ 1. Our findings agree with (and significantly expand on) previously known analytical and numerical results for EFP in quantum liquids. We also discuss interesting universal spacetime features of the instanton solution.

Three-body correlations in nonlinear response of correlated quantum liquid

Behavior of quantum liquids is a fascinating topic in physics. Even in a strongly correlated case, the linear response of a given system to an external field is described by the fluctuation-dissipation relations based on the two-body correlations in the equilibrium. However, to explore nonlinear non-equilibrium behaviors of the system beyond this well-established regime, the role of higher order correlations starting from the three-body correlations must be revealed. In this work, we experimentally investigate a controllable quantum liquid realized in a Kondo-correlated quantum dot and prove the relevance of the three-body correlations in the nonlinear conductance at finite magnetic field, which validates the recent Fermi liquid theory extended to the non-equilibrium regime.

Multiple Superconducting Phases in UTe2: A Complex Analogy to Superfluid Phases of 3He

In quantum liquids, large differences are observed owing to differences in quantum statistics. The physical properties of liquid ³He (Fermion) and ⁴He (Boson) are considerably different at low temperatures. After the discovery of superconductivity in electron (i.e., Fermion) systems, a similar pairing ordered state was expected for ³He. Remarkably, the observed ordered state of ³He was more surprising than expected, multiple superfluid phases in the <em>T-P</em> phase diagram. The origin of the multiple phases was attributed to ferromagnetic interactions in the <em>p</em>-wave symmetry state.