Time evolution of entanglement negativity across a defect
- URL: http://arxiv.org/abs/2001.06274v2
- Date: Wed, 6 May 2020 06:57:29 GMT
- Title: Time evolution of entanglement negativity across a defect
- Authors: Matthias Gruber and Viktor Eisler
- Abstract summary: We consider a quench in a free-fermion chain by joining two homogeneous half-chains via a defect.
The time evolution of the entanglement negativity is studied between adjacent segments surrounding the defect.
We also study a similar quench in the XXZ spin chain via density-matrix renormalization group methods.
- Score: 0.0
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: We consider a quench in a free-fermion chain by joining two homogeneous
half-chains via a defect. The time evolution of the entanglement negativity is
studied between adjacent segments surrounding the defect. In case of equal
initial fillings, the negativity grows logarithmically in time and essentially
equals one-half of the R\'enyi mutual information with index $\alpha = 1/2$ in
the limit of large segments. In sharp contrast, in the biased case one finds a
linear increase followed by the saturation at an extensive value for both
quantities, which is due to the backscattering from the defect and can be
reproduced in a quasiparticle picture. Furthermore, a closer inspection of the
subleading corrections reveals that the negativity and the mutual information
have a small but finite difference in the steady state. Finally, we also study
a similar quench in the XXZ spin chain via density-matrix renormalization group
methods and compare the results for the negativity to the fermionic case.
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