Syljuasen, O. F.Ronnow, H. M.2007-01-242007-01-242007-01-24200010.1088/0953-8984/12/25/104https://infoscience.epfl.ch/handle/20.500.14299/239917We 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.SPIN CORRELATIONSMONTE-CARLOANTIFERROMAGNETTEMPERATUREtext::journal::journal article::research article