241 citations · 953 across the 17 of their papers we have counts for
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Magnetic excitations in two-leg spin 1/2 ladders: experiment and theory
M. Grueninger, M. Windt, T. Nunner +8
Magnetic excitations in two-leg S=1/2 ladders are studied both experimentally and theoretically. Experimentally, we report on the reflectivity, the transmission and the optical con…
Optical spectroscopy of (La,Ca)14Cu24O41 spin ladders: comparison of experiment and theory
M. Grueninger, M. Windt, T. Nunner +8
Transmission and reflectivity of La_x Ca_14-x Cu_24 O_41 two-leg spin-1/2 ladders were measured in the mid-infrared regime between 500 and 12000 1/cm. This allows us to determine t…
Multi-particle excitations and spectral densities in quantum spin-systems
Christian Knetter, Kai P. Schmidt, Götz S. Uhrig
The excitation spectrum of the 2-leg S=1/2 Heisenberg ladder is examined perturbatively. Using an optimally chosen continuous unitary transformation we expand the Hamiltonian and t…
Raman Response in Antiferromagnetic Two-Leg S=1/2 Heisenberg Ladders
Kai P. Schmidt, Christian Knetter, Götz S. Uhrig
The Raman response in the antiferromagnetic 2-leg S=1/2 Heisenberg ladder is calculated for various couplings by continuous unitary transformations. For leg couplings above 80% of…
Fractional and Integer Excitations in Quantum Antiferromagnetic Spin 1/2 Ladders
C. Knetter, K. P. Schmidt, M. Grüninger +1
Spectral densities are computed in unprecedented detail for quantum antiferromagnetic spin 1/2 two-leg ladders. These results were obtained due to a major methodical advance achiev…
Observation of two-magnon bound states in the two-leg ladders of (Ca,La)14Cu24O41
M. Windt, M. Grueninger, T. Nunner +8
Phonon-assisted 2-magnon absorption is studied at T=4 K in the spin-1/2 two-leg ladders of Ca_14-x La_x Cu_24 O_41 (x=5 and 4) for polarization of the electrical field parallel to…