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Magnetic Excitations of Coupled Spin Ladders: a Quantum Monte Carlo Study

Brian M. Andersen·Olav F. Syljuasen
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Abstract

We calculate the magnetic excitation spectrum in the stripe phase of high-T_c materials. The stripes are modeled as coupled spin-1/2 ladders and the spin dynamics is extracted using Quantum Monte Carlo (QMC) simulations, which can capture the strong quantum fluctuations near quantum critical points of coupled spin ladders. We find a characteristic hourglass magnetic excitation spectrum with high-energy peaks rotated by 45 degrees compared to the incommensurate low-energy peaks in good agreement with the experimental data. The excitations are investigated quantitatively as a function of interladder coupling, ladder width, and domain formation with stripe disorder.

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Brian M. Andersen, Olav F. Syljuasen. 2006-08-14. Magnetic Excitations of Coupled Spin Ladders: a Quantum Monte Carlo Study. https://doi.org/10.1103/physrevb.75.012506

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