711 citations · 5.5k across the 188 of their papers we have counts for
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Rung-singlet phase of the S=1/2 two-leg spin-ladder with four-spin cyclic exchange
K. P. Schmidt, H. Monien, G. S. Uhrig
Using continuous unitary transformations (CUT) we calculate the one-triplet gap for the antiferromagnetic S=1/2 two-leg spin ladder with additional four-spin exchange interactions…
Excitations in one-dimensional S=1/2 quantum antiferromagnets
Kai P. Schmidt, Götz S. Uhrig
The transition from dimerized to uniform phases is studied in terms of spectral weights for spin chains using continuous unitary transformations (CUTs). The spectral weights in the…
Charge order induced sharp Raman peak in Sr_14Cu_24O_41
K. P. Schmidt, C. Knetter, M. Grüninger +1
In the two-leg S=1/2 ladders of Sr_14Cu_24O_41 a modulation of the exchange coupling arises from the charge order within the other structural element, the CuO_2 chains. In general,…
Novel Extrapolation for Strong Coupling Expansions
K. P. Schmidt, C. Knetter, G. S. Uhrig
We present a novel extrapolation scheme for high order series expansions. The idea is to express the series, obtained in orders of an external variable, in terms of an internal par…
Renormalization by Continuous Unitary Transformations: One-Dimensional Spinless Fermions
Caspar P. Heidbrink, Götz S. Uhrig
A renormalization scheme for interacting fermionic systems is presented where the renormalization is carried out in terms of the fermionic degrees of freedom. The scheme is based o…