121 citations · 181 across the 3 of their papers we have counts for
3 papers
cond-mat.str-el2002★ 57 cited
Perturbation theories for the S=1/2 spin ladder with four-spin ring exchange
M. Mueller, T. Vekua, H. -J. Mikeska
The isotropic S=1/2 antiferromagnetic spin ladder with additional four-spin ring exchange is studied perturbatively in the strong coupling regime with the help of cluster expansion…
cond-mat.str-el2001★ 3 cited
Cluster expansion for dimerized spin systems
H. -J. Mikeska, M. Mueller
We have studied dimerized spin systems by realizing the cluster expansion to high order. We have extended our previous dimer expansion for one-dimensional systems to cover weakly i…
cond-mat.str-el1998★ 121 cited
Effects of biquadratic exchange on the spectrum of elementary excitations in spin ladders
S. Brehmer, H. -J. Mikeska, M. Mueller +2
We investigate the influence of biquadratic exchange interactions on the low-lying excitations of a S=1/2-ladder using perturbation theory, numerical diagonalization of finite syst…