Quantum entanglement of XY-type spin dimers in Shastry-Sutherland lattice

Abstract

We report a comprehensive study on the origin of the enigmatic disordered ground state within the Shastry-Sutherland lattice, BaCe${}_2$ZnS${}_5$, at low temperatures. The magnetization and heat capacity data show a lack of magnetic ordering down to 73 mK. We deploy a localized spin dimer model which can accurately reproduce the dynamic structure factor of the neutron data, magnetization and heat capacity data. Remarkably, the intra-dimer exchange interaction shows strong XY-type anisotropy and the ground state of BaCe${}_2$ZnS${}_5$ is in an entangled state $(|\uparrow \uparrow >-|\downarrow \downarrow >)/\sqrt{2}$. This is in contrast to the singlet dimer state that is obtained for Heisenberg interactions. These results confirm that BaCe${}_2$ZnS${}_5$ is in a quantum paramagnet state consisting of entangled spin dimer states.

References in corpus (13)

• Fractional magnetization plateaus and magnetic order in the Shastry Sutherland magnet TmB4
• A quantum magnetic analogue to the critical point of water
• Structural Fluctuations in the Spin Liquid State of Tb2Ti2O7
• Spin-stretching modes in anisotropic magnets: spin-wave excitations in the multiferroic Ba2CoGe2O7
• The case for a U(1)${}_{\pi }$ Quantum Spin Liquid Ground State in the Dipole-Octupole Pyrochlore Ce${}_2$Zr${}_2$O${}_7$
• Hybridized quadrupolar excitations in the spin-anisotropic frustrated magnet FeI2
• Sleuthing out exotic quantum spin liquidity in the pyrochlore magnet Ce${}_2$Zr${}_2$O${}_7$
• Magnetic properties of the Shastry-Sutherland lattice material BaNd${}_2$ZnO${}_5$
• Local magnetic anisotropy by polarized neutron powder diffraction: application of magnetically induced preferred crystallite orientation
• Bose-Einstein condensation of a two-magnon bound state in a spin-one triangular lattice
• Field-Induced Partial Disorder in a Shastry-Sutherland Lattice
• Single crystal synthesis and magnetic properties of a Shastry-Sutherland lattice compound BaNd2ZnS5
• Partial flux ordering and thermal Majorana metals in (higher-order) spin liquids