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Quantum renormalization of high energy excitations in the 2D Heisenberg antiferromagnet

Olav F. Syljuasen·Henrik M. Ronnow
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Abstract

We find using Monte Carlo simulations of the spin-1/2 2D square lattice nearest neighbour quantum Heisenberg antiferromagnet that the high energy peak locations at (pi,0) and (pi/2,pi/2) differ by about 6%, (pi/2,pi/2) being the highest. This is a deviation from linear spin wave theory which predicts equal magnon energies at these points.

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Olav F. Syljuasen, Henrik M. Ronnow. 2000-06-19. Quantum renormalization of high energy excitations in the 2D Heisenberg antiferromagnet. https://doi.org/10.1088/0953-8984%2F12%2F25%2F104

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