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arXiv · 2104.10913

Entanglement Entropy with Lifshitz Fermions

Dion Hartmann·Kevin Kavanagh·Stefan Vandoren
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Abstract

We investigate fermions with Lifshitz scaling symmetry and study their entanglement entropy in 1+1 dimensions as a function of the scaling exponent $z$. Remarkably, in the ground state the entanglement entropy vanishes for even values of $z$, whereas for odd values it is independent of $z$ and equal to the relativistic case with $z=1$. We show this using the correlation method on the lattice, and also using a holographic cMERA approach. The entanglement entropy in a thermal state is a more detailed function of $z$ and $T$ which we plot using the lattice correlation method. The dependence on the even- or oddness of $z$ still shows for small temperatures, but is washed out for large temperatures or large values of $z$.

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Dion Hartmann, Kevin Kavanagh, Stefan Vandoren. 2021-04-22. Entanglement Entropy with Lifshitz Fermions. https://doi.org/10.21468/scipostphys.11.2.031

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