Hidden phases born of a quantum spin liquid: Application to pyrochlore spin ice

Quantum spin liquids (QSL) have been focused as promising ground states of the frustrated magnets supporting fractionalized quasi-particles with the emergent gauge structures. Plenty of such deconfined phases turn out to be quite stable against weak perturbations, whereas the strong coupling drives the system to be conventionally ordered. However, this standard instruction of the lattice gauge theory leaves an open question on the intermediate regime between deconfined and fully-confined limits. Here, we formulate the effective parton interactions to explore the hidden phases beyond the perturbative approach. We show that the intermediate coupling generically arouses novel phases whose gauge structure is partially lifted before the full confinement. By reformulating the pyrochlore spin model, abundant daughter phases including Z2 QSLs and a spinon supersolid descended from U(1) QSL are proposed with experimental signatures. We discuss the relevant numerical results supporting our formalism as a platform for searching new exotic phases of matter in frustrated magnets.