5 papers
Introduction to the Bethe Ansatz III
Michael Karbach, Kun Hu, Gerhard Muller
Having introduced the magnon in part I and the spinon in part II as the relevant quasi-particles for the interpretation of the spectrum of low-lying excitations in the one-dimensio…
Computational probes of collective excitations in low-dimensional magnetism
Gerhard Muller, Michael Karbach
The investigation of the dynamics of quantum many-body systems is a concerted effort involving computational studies of mathematical models and experimental studies of material sam…
Introduction to the Bethe ansatz I
Michael Karbach, Gerhard Muller
The Bethe ansatz for the one-dimensional s=1/2 Heisenberg ferromagnet is introduced at an elementary level. The presentation follows Bethe's original work very closely. A detailed…
Gap's in the antiferromagnetic Heisenberg model
A. Fledderjohann, M. Karbach, K. -H. Mütter
We study the one-dimensional spin-1/2 antiferromagnetic Heisenberg model exposed to an external field, which is a superposition of a homogeneous field and a small periodic…
Static and dynamic structure factors in the Haldane phase of the bilinear-biquadratic spin-1
K-H Muetter, A Schmitt, M Karbach +2
The excitation spectra of the T=0 dynamic structure factors for the spin, dimer, and trimer fluctuation operators as well as for the newly defined center fluctuation operator in th…