title: Quantum melting of spin ice: emergent cooperative quadrupole and chirality.
abstract: Quantum melting of spin ice is proposed for pyrochlore-lattice magnets Pr2TM2O7 (TM=Ir, Zr, and Sn). The quantum superexchange Hamiltonian having a nontrivial magnetic anisotropy is derived on the basis of atomic non-Kramers magnetic doublets. The ground states exhibit a cooperative ferroquadrupole and pseudospin chirality, forming a magnetic analog of smectic liquid crystals. Our theory accounts for dynamic spin-ice behaviors experimentally observed in Pr2TM2O7.
authors.affiliation: Condensed Matter Theory Laboratory, RIKEN, 2-1, Hirosawa, Wako 351-0198, Saitama, Japan.
authors.forename: Shigeki
authors.initials: S
authors.lastname: Onoda
authors.forename: Yoichi
authors.initials: Y
authors.lastname: Tanaka