Beyond Conventional Pairing: Bosonic Quartic Superfluidity, Exotic XY Magnetism, and Phase Criticality

TL;DR

This paper introduces two novel bosonic quartic superfluid phases with high-order correlations in binary boson mixtures, revealing new quantum critical points, magnetic states, and proposing experimental detection methods, thus expanding the understanding of quantum matter.

Contribution

The study uncovers bosonic quartic superfluid phases and associated quantum criticality, extending the paradigm of superfluidity through high-order correlations and synthetic interactions.

Findings

Identification of bosonic quartic superfluid phases with four-particle correlations

Discovery of a quantum quadruple critical point and state-dependent criticality

Proposal of momentum-resolved noise correlation spectroscopy for experimental detection

Abstract

We report two unprecedented bosonic quartic superfluid (BQSF) phases in binary boson mixtures with synthetic pair-hopping (SPH) interaction realizable through Floquet engineering, transcending the conventional bosonic superfluidity paradigm via high-order correlations. Through extensive numerical simulations, we demonstrate: (i) The paired super-counter-fluid (PSCF) phase that exhibits bosonic 'four-particle' correlations, directly mirroring fermionic 4e superconductivity; (ii) The symbiotic super-counter-fluid which is an anomalous quantum phase featuring intrinsically intertwined, non-zero PSCF and super-counter-fluid orders. Both phases further reveal unreported pseudo-spin-ordered XY ferromagnetic states with filling-dependent magnetization textures. Adjacent to BQSF phases, we uncover both a previously unreported quantum quadruple critical point induced by interexchange asymmetry and SPH-driven state-dependent criticality-the latter exhibiting distinct behavior from conventional two-component bosonic systems. We propose momentum-resolved noise correlation spectroscopy-building on established quantum gas microscopy techniques-as a direct probe for the characteristic signatures of these BQSF states. Our results establish a new paradigm in quantum matter, opening unprecedented avenues to explore (i) quartic quantum coherence, (ii) emergent collective phenomena, and (iii) extended XY magnetism-resolving a longstanding classification challenge while discove