Doctor of Philosophy (PhD)
First Committee Member
Number of Pages
The goal of this project is to study the ground-state properties of frustrated spin-1/2 two- and three-leg Heisenberg ladders, and to investigate possible effects of diagonal couplings on spin gaps. The ground-state and the first-excited-state energies of these two systems are calculated systematically by using the density matrix renormalization group method. The ground state phase diagrams for these two systems are obtained. For the frustrated two-leg ladder, we found that the spin gap is insensitive to the change of the FM diagonal coupling constant. This is in agreement with experimental suggestions. For the frustrated three-leg ladder, we conclusively proved that introducing AF diagonal couplings can not change the gapless property of the ground state.
Antiferromagnetic; Frustrated; Heisenberg; Heisenberg Ladders; Ladders; Leg; Phase Diagrams; Spin; Spin-1/2
Condensed matter; Physics
University of Nevada, Las Vegas
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Zhu, Ningsheng, "Frustrated spin -1/2 two-leg and three-leg antiferromagnetic Heisenberg ladders" (2000). UNLV Retrospective Theses & Dissertations. 3109.
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