Novel Strongly Spin-Orbit Coupled Quantum Dimer Magnet: Yb${}_2$Si${}_2$O${}_7$

Abstract

The quantum dimer magnet (QDM) is the canonical example of quantum magnetism. The QDM state consists of entangled nearest-neighbor spin dimers and often exhibits a field-induced triplon Bose-Einstein condensate (BEC) phase. We report on a new QDM in the strongly spin-orbit coupled, distorted honeycomb-lattice material Yb${}_2$Si${}_2$O${}_7$. Our single crystal neutron scattering, specific heat, and ultrasound velocity measurements reveal a gapped singlet ground state at zero field with sharp, dispersive excitations. We find a field-induced magnetically ordered phase reminiscent of a BEC phase, with exceptionally low critical fields of $H_{c1}\sim 0.4$ T and $H_{c2}\sim 1.4$ T. Using inelastic neutron scattering in an applied magnetic field we observe a Goldstone mode (gapless to within $\delta E$ = 0.037 meV) that persists throughout the entire field-induced magnetically ordered phase, suggestive of the spontaneous breaking of U(1) symmetry expected for a triplon BEC. However, in contrast to other well-known cases of this phase, the high-field ($\mu$${}_0$$H\ge 1.2$T) part of the phase diagram in Yb${}_2$Si${}_2$O${}_7$ is interrupted by an unusual regime signaled by a change in the field dependence of the ultrasound velocity and magnetization, as well as the disappearance of a sharp anomaly in the specific heat. These measurements raise the question of how anisotropy in strongly spin-orbit coupled materials modifies the field induced phases of QDMs.

arXiv comment6 pages, 4 figures, 12 pages of Supplemental Information, 15 Supplemental figures. Updated to published version

References in corpus (29)

• Double-slit photoelectron interference in strong-field ionization of the neon dimer
• Anyons in an exactly solved model and beyond
• Mott Insulators in the Strong Spin-Orbit Coupling Limit: From Heisenberg to a Quantum Compass and Kitaev Models
• Bose-Einstein Condensation in Magnetic Insulators
• Pyrochlore Photons: The U(1) Spin Liquid in a S=1/2 Three-Dimensional Frustrated Magnet
• Linear spin wave theory for single-Q incommensurate magnetic structures
• On the Origin of Zigzag Magnetic Order in Iridium Oxide Na2IrO3
• Quantum Spin Ice: A Search for Gapless Quantum Spin Liquids in Pyrochlore Magnets
• Quantum Excitations in Quantum Spin Ice
• Thermodynamics and spin gap of the Heisenberg ladder calculated by the look-ahead Lanczos algorithm
• Magnetic Field-Induced Condensation of Triplons in Han Purple Pigment BaCuSi${}_2$O${}_6$
• The new Cold Neutron Chopper Spectrometer at the Spallation Neutron Source - Design and Performance
• Bose-Einstein Condensation of S = 1 Ni spin degrees of freedom in NiCl2-4SC(NH2)2
• Valence Bonds in Random Quantum Magnets: Theory and Application to YbMgGaO4
• Hidden symmetries of the extended Kitaev-Heisenberg model: Implications for honeycomb lattice iridates A2IrO3
• Quantum Melting of Spin Ice: Emergent Cooperative Quadrupole and Chirality
• Frustration and anisotropic exchange in ytterbium magnets with edge-shared octahedra
• Field-induced Bose-Einstein Condensation of triplons up to 8 K in Sr3Cr2O8
• Orbital-Exchange and Fractional Quantum Number Excitations in an f-electron Metal Yb${}_2$Pt${}_2$Pb
• Kitaev materials beyond iridates: order by quantum disorder and Weyl magnons in rare-earth double perovskites
• Anisotropic exchange within decoupled tetrahedra in the quantum breathing pyrochlore Ba3Yb2Zn5O11
• Quantum fluctuations and strong mass renormalization in NiCl2-4SC(NH2)2
• Bose-Einstein Condensation of Triplons in Ba3Cr2O8
• Evidence for gapped spin-wave excitations in the frustrated Gd2Sn2O7 pyrochlore antiferromagnet from low-temperature specific heat measurements
• Ordered magnetic phases of the frustrated spin-dimer compound Ba3Mn2O8
• Character of magnetic excitations in a quasi-one-dimensional antiferromagnet near the quantum critical points: Impact on magneto-acoustic properties
• Universal Dynamic Magnetism in Yb-Pyrochlores with Disparate Ground States
• Field-induced long-range magnetic order in the spin-singlet ground state system YbAl3C3: Neutron diffraction study
• Singlet-triplet Crossover in the Two-dimensional Dimer Spin System YbAl3C3

Cited by in corpus (19)

• Field-induced magnetic transition and spin fluctuation in quantum spin liquid candidate CsYbSe${}_2$
• Tomonaga-Luttinger Liquid Behavior and Spinon Confinement in YbAlO${}_3$
• Synthesis and Anisotropic Magnetism in Quantum Spin Liquid Candidates $A$YbSe${}_2$ ($A$ = K and Rb)
• Unravelling competing microscopic interactions at a phase boundary: a single crystal study of the metastable antiferromagnetic pyrochlore Yb${}_2$Ge${}_2$O${}_7$
• Spin liquid state in a rare-earth hyperkagome lattice
• On two phases inside the Bose condensation dome of Yb${}_2$Si${}_2$O${}_7$
• Experimental observation of magnetic dimers in diluted Yb:YAlO${}_3$
• Magnon Condensation in Dimerized Antiferromagnets with Spin-Orbit Coupling
• Magnetic properties of a spin-orbit entangled Jeff = 1/2 honeycomb lattice
• Magnetic Properties of the Ising-like Rare Earth Pyrosilicate: D-Er${}_2$Si${}_2$O${}_7$
• Bose-Einstein condensation in honeycomb dimer magnets and $\mathrm{Y}{\mathrm{b}}_2\mathrm{S}{\mathrm{i}}_2{\mathrm{O}}_7$
• Crystal field effects in the zig-zag chain compound SrTm${}_2$O${}_4$
• Higher-order topology and corner triplon excitations in two-dimensional quantum spin-dimer models
• Néel Ordering in the Distorted Honeycomb Pyrosilicate: C-Er${}_2$Si${}_2$O${}_7$
• Magnetic structure, excitations and field induced transitions in the honeycomb lattice $\mathrm{E}{\mathrm{r}}_2\mathrm{S}{\mathrm{i}}_2{\mathrm{O}}_7$
• Pulsed Neutron Spectroscopy of Low Dimensional Magnets: Past, Present, and Future
• Quasi-Two-Dimensional Quantum Antiferromagnetism in the Distorted Honeycomb Compound KCuIn(PO4)2
• Finite Spinon Density-of-States in Triangular-Lattice Delafossite TlYbSe${}_2$
• Localized Triplons and Site Stuffing in the Quantum Dimer Magnet BiYbGeO${}_5$