相关论文: Novel bipartite entanglement in the quantum dimer …
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…
We present the magnetic properties of a strongly spin-orbit coupled quantum dimer magnet based on Co$^{2+}$. The metal-organic framework compound Co$_2$(BDC)$_2$(DPTTZ)$_2$$\cdot$DMF features Co$^{2+}$ dimers arranged nearly orthogonal to…
The bipartite quantum and thermal entanglement is quantified within pure and mixed states of a mixed spin-(1/2,1) Heisenberg dimer with the help of negativity. It is shown that the negativity, which may serve as a measure of the bipartite…
Quantum entanglement effects between the electronic spin and charge degrees of freedom are examined in an organic molecular solid, termed a dimer-Mott insulating system, in which molecular dimers are arranged in a crystal as fundamental…
We delineate quantum magnetism in the strongly spin-orbit coupled, distorted honeycomb-lattice antiferromagnet BiYbGeO$_{5}$. Our magnetization and heat capacity measurements reveal that its low-temperature behavior is well described by an…
The interplay between spin-orbit coupling, anisotropic magnetic interaction, frustration-induced quantum fluctuations and spin correlations can lead to novel quantum states with exotic excitations in rare-earth-based quantum magnets.…
Sr$_{3}$Cr$_{2}$O$_{8}$ consist of a lattice of spin-1/2 Cr$^{5+}$ ions, which form hexagonal bilayers and which are paired into dimers by the dominant antiferromagnetic intrabilayer coupling. The dimers are coupled three-dimensionally by…
We present a comprehensive experimental investigation of Yb magnetic dimers in Yb$_{0.04}$Y$_{0.96}$AlO$_3$, an Yb-doped Yttrium Aluminum Perovskite (YAP) YAlO$_3$ by means of specific heat, magnetization and high-resolution inelastic…
We present specific-heat and neutron-scattering results for the \emph{S}=1/2 quantum antiferromagnet (dimethylammonium)(3,5-dimethylpyridinium)CuBr$_4$. The material orders magnetically at \emph{T}$_N$=1.99(2)\,K, and magnetic excitations…
We derive a quantum spin Hamiltonian of the spin-1/2 zigzag chain realized in a rare earth ytterbium-based magnetic insulator, YbCuS2. This material undergoes a transition at 0.95K to an incommensurate magnetic phase with small moments,…
We apply density functional theory band structure calculations and quantum Monte Carlo simulations to investigate the Bose-Einstein condensation in the spin-1/2 quantum magnet Pb2V3O9. In contrast to previous conjectures on the…
We report results of magnetization, specific-heat and muon-spin relaxation measurements on single crystals of disorder-free Yb$^{3+}$ triangular lattice Yb(BaBO$_3$)$_3$. The magnetization experiments show anisotropic magnetic properties…
The ytterbium pyrochlore magnets, Yb2B2O7 (B = Sn, Ti, Ge) are well described by S_eff = 1/2 quantum spins decorating a network of corner-sharing tetrahedra and interacting via anisotropic exchange. Structurally, only the non-magnetic…
Neutron scattering measurements on the pyrochlore magnet Ce$_2$Zr$_2$O$_7$ reveal an unusual crystal field splitting of its lowest $J$=5/2 multiplet, such that its ground state doublet is composed of m$_J$=$\pm$3/2, giving these doublets a…
Thermodynamic and muon spin-relaxation measurements have recently highlighted BiYbGeO$_5$ as a new example of a rare-earth-based quantum dimer magnet with isolated Yb$^{3+}$ spin-$\frac{1}{2}$ dimers. However, direct spectroscopic evidence…
Frustration-induced strong quantum fluctuations accompanied by spin-orbit coupling and crystal electric field can give rise to rich and diverse magnetic phenomena associated with unconventional low-energy excitations in rare-earth based…
The interplay of crystal electric field, temperature, and spin-orbit coupling can yield a Kramers ion and thus an effective S = 1/2 ground state for Co2+ ions (3d7), which is often the case for low dimensional materials. This is because a…
The measure of quantum entanglement is determined for any dimer, either ferromagnetic or antiferromagnetic, spin-1/2 Heisenberg systems in the presence of external magnetic field. The physical quantity proposed as a measure of thermal…
Shastry-Sutherland magnet is a typical frustrated spin system hosting rich phases. While the Heisenberg limit has been extensively studied, the role of spin-orbit coupling is not well explored. Motivated by newly discovered rare-earth…
We examine the magnetic field dependent excitations of the dimerized spin-1/2 chain, copper nitrate, with antiferromagnetic intra-dimer exchange $J_1=0.44$ meV and exchange alternation $\alpha=J_2/J_1=0.24$. Magnetic excitations in three…