Tacon, M. Le, Forrest, T. R., Rüegg, Ch., Bosak, A., Walters, A. C., Mittal, R., ...
We report inelastic x-ray scattering experiments on the lattice dynamics in SmFeAsO and superconducting SmFeAsO$_{0.6}$F$_{0.35}$ single crystals. Particular attention was paid to the dispersions...
Direct Observation of Magnon Fractionalization in the Quantum Spin Ladder (2008)
Thielemann, B., Rüegg, Ch., Rønnow, H. M., Läuchli, A. M., Normand, B., ...
We measure by inelastic neutron scattering the spin excitation spectra as a function of applied magnetic field in the quantum spin-ladder material (C5H12N)2CuBr4. Discrete magnon modes at low fields...
Quantum magnets under pressure: controlling elementary excitations in TlCuCl₃ (2008)
Rüegg, Ch., Normand, Bruce, Matsumoto, M., Furrer, A., McMorrow, D. F., Krämer, K. W., ...
We follow the evolution of the elementary excitations of the quantum antiferromagnet TlCuCl₃ through the pressure-induced quantum critical point, which separates a dimer-based quantum disordered...
Quantum magnets under pressure: controlling elementary excitations in TlCuCl₃ (2008)
Rüegg, Ch., Normand, Bruce, Matsumoto, M., Furrer, A., McMorrow, D. F., Krämer, K. W., ...
We follow the evolution of the elementary excitations of the quantum antiferromagnet TlCuCl₃ through the pressure-induced quantum critical point, which separates a dimer-based quantum disordered...
Field-Controlled Magnetic Order in the Quantum Spin-Ladder System (Hpip)2CuBr4 (2008)
Thielemann, B., Rüegg, Ch., Kiefer, K., Rønnow, H. M., Normand, B., Bouillot, P., ...
Neutron diffraction is used to investigate the field-induced, antiferromagnetically ordered state in the two-leg spin-ladder material (Hpip)2CuBr4. This "classical" phase, a consequence of weak...
Thermodynamics of the Spin Luttinger-Liquid in a Model Ladder Material (2008)
Rüegg, Ch., Kiefer, K., Thielemann, B., McMorrow, D. F., Zapf, V., Normand, B., ...
The phase diagram in temperature and magnetic field of the metal-organic, two-leg, spin-ladder compound (C5H12N)2CuBr4 is studied by measurements of the specific heat and the magnetocaloric effect....
Quantum Magnets under Pressure: Controlling Elementary Excitations in TlCuCl3 (2008)
Rüegg, Ch., Normand, B., Matsumoto, M., Furrer, A., McMorrow, D., Krämer, K., ...
We follow the evolution of the elementary excitations of the quantum antiferromagnet TlCuCl3 through the pressure-induced quantum critical point, which separates a dimer-based quantum disordered...
Bose-Einstein Condensation in Magnetic Insulators (2007)
Giamarchi, T., Rüegg, Ch., Tchernyshyov, O.
The elementary excitations in antiferromagnets are magnons, quasiparticles with integer spin and Bose statistics. In an experiment their density is controlled efficiently by an applied magnetic field...
Quantum statistics of interacting dimer spin systems (2006)
Rüegg, Ch., Normand, Bruce, Matsumoto, M., Niedermayer, Ch., Furrer, A., Krämer, K. W., ...
The compound TlCuCl₃ represents a model system of dimerized quantum spins with strong interdimer interactions. We investigate the triplet dispersion as a function of temperature by inelastic...
Quantum statistics of interacting dimer spin systems (2006)
Rüegg, Ch., Normand, Bruce, Matsumoto, M., Niedermayer, Ch., Furrer, A., Krämer, K. W., ...
The compound TlCuCl₃ represents a model system of dimerized quantum spins with strong interdimer interactions. We investigate the triplet dispersion as a function of temperature by inelastic...
Multiple Magnon Modes and Consequences for the Bose-Einstein Condensed Phase in BaCuSi2O6 (2006)
Rüegg, Ch., McMorrow, D. F., Normand, B., Ronnow, H. M., Sebastian, S. E., Fisher, I. R., ...
The compound BaCuSi2O6 is a quantum magnet with antiferromagnetic dimers of S = 1/2 moments on a quasi-2D square lattice. We have investigated its spin dynamics by inelastic neutron scattering...
Quantum Statistics of Interacting Dimer Spin Systems (2005)
Rüegg, Ch., Normand, B., Matsumoto, M., Niedermayer, Ch., Furrer, A., Krämer, K. W., ...
The compound TlCuCl3 represents a model system of dimerized quantum spins with strong interdimer interactions. We investigate the triplet dispersion as a function of temperature by inelastic neutron...