Related papers: Far infrared study of the two dimensional dimer sp…
Various spin gap excitations have been observed in the two-dimensional dimer system SrCu_2(BO_3)_2 by means of submillimeter wave ESR. The zero-field energy gap of the lowest spin gap excitation shows a splitting into two triplet modes and…
We report results of 11B NMR and susceptibility measurements on the quasi 2D frustrated dimer spin system SrCu2(BO3)2 under high pressure. At 2.4 GPa and in a magnetic field of 7 T, NMR lines split with decreasing temperature in two steps.…
We have studied spin excitation spectra in the Shastry-Sutherland model compound SrCu$_2$(BO$_3$)$_2$ in magnetic fields using far-infrared Fourier spectroscopy. The transitions from the ground singlet state to the triplet state at 24…
We report magnetization and heat capacity measurements of single crystal samples of the spin gap compound Sr$_2$Cu(BO$_3$)$_2$. Low-field data show that the material has a singlet ground state comprising dimers with intradimer coupling J =…
The excited state energy spectrum of a two-dimensional dimer system SrCu$_2$(BO$_3$)$_2$ has been investigated by high field ESR. Various types of multiple-triplet bound states-excited singlet, triplet and quintet states are identified,…
We report results of nuclear magnetic resonance (NMR) experiments in SrCu2(BO3)2, a quasi two-dimensional spin system with a singlet ground state. When magnetic field is applied along the c-axis, each of the quadrupole split Cu resonance…
The quasi-two-dimensional Heisenberg spin $S=1/2$ dimer system bis(2-amino-5-fluoro-pyridinium) tetrachlorocuprate(II) is studied by means of inelastic neutron scattering, calorimetry and nuclear magnetic resonance (NMR) experiments. In the…
Effects of the inter-layer couplings for the orthogonal dimer system SrCu$_2$(BO$_3$)$_2$ are discussed. The spin-gap $\Delta$ of the three-dimensional model is independent of the inter-layer couplings when they are small. Therefore at low…
We perform a low temperature Raman scattering study of phononic and collective spin excitations in the orthogonal dimers compound SrCu_2(BO_3)_2, focussing on the symmetry and the effects of external fields on the magnetic modes. The zero…
Magnetic excitations in the isostructural spin-dimer systems Sr3Cr2O8 and Ba3Cr2O8 are probed by means of high-field electron spin resonance at sub-terahertz frequencies. Three types of magnetic modes were observed. One mode is gapless and…
High resolution neutron scattering measurements on a single crystal of SrCu(2-x)Mgx(BO3)2 with x=0.05 reveal the presence of new spin excitations within the gap of this quasi-two dimensional, singlet ground state system. Application of a…
A displacive, 2nd order structural phase transition at Ts=395 K from space group I`4 2 m below Ts to I 4/m c m above Ts has been discovered in the two-dimensional spin dimer compound SrCu2(BO3)2. The temperature evolution of the structure…
The two dimensional Heisenberg model for SrCu_2(BO_3)_2 has the exact dimer ground state which was proven by Shastry and Sutherland almost twenty years ago. The critical value of the quantum phase transition from the dimer state to the…
We report the observation of magnetic superstructure in a magnetization plateau state of SrCu2(BO3)2, a frustrated quasi-two-dimensional quantum spin system. The Cu and B nuclear magnetic resonance (NMR) spectra at 35 mllikelvin indicate an…
Using scanning tunneling spectroscopy (STS) at 5 K in B-fields up to 7 T, we investigate the local density of states of a two-dimensional electron system (2DES) created by Cs adsorption on p-type InSb(110). The 2DES, which in contrast to…
Magnetic excitations of the recently discovered frustrated spin-1/2 two-leg ladder system Li$_2$Cu$_2$O(SO$_4$)$_2$ are investigated using inelastic neutron scattering, magnetic susceptibility and infrared absorption measurements. Despite…
We present a Raman light scattering study of the two-dimensional quantum spin system SrCu2(BO3)2 and show that the magnetic excitation spectrum has a rich structure, including several well-defined bound state modes at low temperature, and a…
The mineral malachite, Cu2(OD)2CO3, has a quantum spin-liquid ground state and no long-range magnetic order down to at least T=0.4 K. Inelastic neutron scattering measurements show that the excitation spectrum consists of dispersive gapped…
Quantum magnetic materials can provide explicit realizations of paradigm models in quantum many-body physics. In this context, SrCu$_2$(BO$_3$)$_2$ is a faithful realization of the Shastry-Sutherland model (SSM) for ideally frustrated spin…
The temperature and high magnetic field dependence of the longitudinal soundwave mode c_{11} in the two dimensional dimer system SrCu_{2}(BO_{3})_{2} is presented. c_{11}(T) shows anomalies due to strong interdimer spin-strain coupling. We…