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arXiv · 1809.06747

Simulating excitation spectra with projected entangled-pair states

Laurens Vanderstraeten·Jutho Haegeman·Frank Verstraete
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Abstract

We develop and benchmark a technique for simulating excitation spectra of generic two-dimensional quantum lattice systems using the framework of projected entangled-pair states (PEPS). The technique relies on a variational ansatz for capturing quasiparticle excitations on top of a PEPS ground state. Our method perfectly captures the quasiparticle dispersion relation of the square-lattice transverse-field Ising model, and reproduces the spin-wave velocity and the spin-wave anomaly in the square-lattice Heisenberg model with high precision.

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Laurens Vanderstraeten, Jutho Haegeman, Frank Verstraete. 2018-09-18. Simulating excitation spectra with projected entangled-pair states. https://doi.org/10.1103/physrevb.99.165121

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