Related papers: Impurity-induced singlet breaking in SrCu2(BO3)2
We report a comprehensive temperature-dependent investigation of the 1:2 ordered triple perovskite system Sr$_3$CaRu$_2$O$_9$. It crystallizes in the monoclinic structure with space group $P21/c$, consisting of corner-sharing CaO$_6$ and…
Disorder is ubiquitous in any quantum many-body system and is usually considered to be an obstacle to the elucidation of the underlying physics of complex systems, but its presence can often introduce exotic phases of matter that cannot…
We report that MoX3 (X = I, Br) are rare van der Waals materials that exhibit signatures of both quantum spin chains with a spin singlet ground state and classical Neel order. Bulk single crystals grown by chemical vapor transport exhibit…
We report muon spin relaxation ($\mu$SR) measurements of optimally-doped and overdoped Bi$_{2+x}$Sr$_{2-x}$CaCu$_2$O$_{8+\delta}$ (Bi2212) single crystals that reveal the presence of a weak temperature-dependent quasi-static internal…
The S=1/2 Heisenberg spin chain compound SrCuO2 doped with different amounts of nickel (Ni), palladium (Pd), zinc (Zn) and cobalt (Co) has been studied by means of Cu nuclear magnetic resonance (NMR). Replacing only a few of the S=1/2 Cu…
We report muon-spin rotation/relaxation (muSR) measurements on single crystals of the electron-doped high-T_c superconductor Pr$_{2-x}$Ce$_x$CuO$_4$. In zero external magnetic field, superconductivity is found to coexist with Cu spins that…
Superconductors that possess both broken spatial inversion symmetry and spin-orbit interactions exhibit a mix of spin singlet and triplet pairing. Here, we report on measurements of the superconducting properties of electron-doped, strained…
The S=1/2 spin chain material SrCuO2 doped with 1% S=1 Ni-impurities is studied by inelastic neutron scattering. At low temperatures, the spectrum shows a pseudogap \Delta ~ 8 meV, absent in the parent compound, and not related to any…
The study of interacting spin systems is of fundamental importance for modern condensed matter physics. On frustrated lattices, magnetic exchange interactions cannot be simultaneously satisfied, and often give rise to competing exotic…
We report a random singlet ground state in the $S=\frac{1}{2}$ Heisenberg pyrochlore antiferromagnet NaCdCu$_2$F$_7$. Cationic Na$^+$/Cd$^{2+}$ disorder on the pyrochlore $A$ site generates a broad distribution of…
Magnetic susceptibility and specific heat versus temperature measurements on polycrystalline samples of Sr3Cr2O8 and the isostructural, nonmagnetic compound Sr3V2O8 are reported. A Curie-Wiess fit to the high-temperature susceptibility data…
TlCuCl$_3$ is a coupled spin dimer system, which has a singlet ground state with an excitation gap of $\Delta/g\mu_{\mathrm B}$ = 5.5 T. TlCu$_{1-x}$Mg$_x$Cl$_3$ doped with nonmagnetic Mg$^{2+}$ ions undergoes impurity-induced magnetic…
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 semi-metallic behavior of the perovskite iridate SrIrO3 shifts the end-member of the strongly spin-orbit (SO) coupled Ruddlesden-Popper series Srn+1IrnO3n+1 away from the Mott insulating regime and the half-filled pseudospin Jeff=1/2…
Magnetic properties of a one-dimensional frustrated quantum spin system Rb2Cu2Mo3O12 is investigated by the muon spin relaxation (muSR) technique. Although this system shows an incommensurate spin correlation in neutron scattering, it has…
Spinon-magnon mixing was recently reported in botallackite Cu$_2$(OH)$_3$Br with a uniaxially compressed triangular lattice of Cu$^{2+}$ quantum spins [Zhang et al., Phys. Rev. Lett. 125, 037204 (2020)]. Its nitrate counterpart rouaite,…
Recent nuclear magnetic resonance studies [A. Pustogow {\it et al.}, arXiv:1904.00047] have challenged the prevalent chiral triplet pairing scenario proposed for Sr$_2$RuO$_4$. To provide guidance from microscopic theory as to which other…
The spin-chain compound Sr3NiPtO6 is known to have a nonmagnetic ground state. We have investigated the nature of ground state of Sr3NiPtO6 using magnetic susceptibility $\chi(T)$, heat capacity $C_{\rm p}(T)$, muon spin relaxation…
We have measured the spin susceptibility of the underdoped high temperature superconductor, YBa2Cu4O8 by Gd^{3+} electron spin resonance in single crystals and aligned powders at several magnetic fields between 3 and 15.4 T. At low…
$^{63}$Cu and $^{199}$Hg NMR shifts for an optimally and underdoped HgBa$_{2}$CuO$_{4+\delta}$ single crystal are reported, and the temperature dependence dictates a two-component description of the uniform spin susceptibility. The first…