Can we always get the entanglement entropy from the Kadanoff-Baym equations? The case of the T-matrix approximation
(2011) In Europhysics Letters 95(2).- Abstract
- We study the time-dependent transmission of entanglement entropy through an out-of-equilibrium model interacting device in a quantum transport set-up. The dynamics is performed via the Kadanoff-Baym equations within many-body perturbation theory. The double occupancy <(n) over cap (R dagger)(n) over cap (R down arrow)>, needed to determine the entanglement entropy, is obtained from the equations of motion of the single-particle Green's function. A remarkable result of our calculations is that <(n) over cap (R dagger)(n) over cap (R down arrow)> can become negative, thus not permitting to evaluate the entanglement entropy. This is a shortcoming of approximate, and yet conserving, many-body self-energies. Among the tested... (More)
- We study the time-dependent transmission of entanglement entropy through an out-of-equilibrium model interacting device in a quantum transport set-up. The dynamics is performed via the Kadanoff-Baym equations within many-body perturbation theory. The double occupancy <(n) over cap (R dagger)(n) over cap (R down arrow)>, needed to determine the entanglement entropy, is obtained from the equations of motion of the single-particle Green's function. A remarkable result of our calculations is that <(n) over cap (R dagger)(n) over cap (R down arrow)> can become negative, thus not permitting to evaluate the entanglement entropy. This is a shortcoming of approximate, and yet conserving, many-body self-energies. Among the tested perturbation schemes, the T-matrix approximation stands out for two reasons: it compares well to exact results in the low-density regime and it always provides a non-negative <(n) over cap (R dagger)(n) over cap (R down arrow)> For the second part of this statement, we give an analytical proof. Finally, the transmission of entanglement across the device is diminished by interactions but can be amplified by a current flowing through the system. Copyright (C) EPLA, 2011 (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/2032317
- author
- Puig von Friesen, Marc LU ; Verdozzi, Claudio LU and Almbladh, Carl-Olof LU
- organization
- publishing date
- 2011
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Europhysics Letters
- volume
- 95
- issue
- 2
- article number
- 27005
- publisher
- EDP Sciences
- external identifiers
-
- wos:000292384900024
- scopus:79960153949
- ISSN
- 0295-5075
- DOI
- 10.1209/0295-5075/95/27005
- language
- English
- LU publication?
- yes
- id
- 58f43f29-ae38-4570-b6d0-b4191501d847 (old id 2032317)
- date added to LUP
- 2016-04-01 10:30:36
- date last changed
- 2023-09-14 05:26:29
@article{58f43f29-ae38-4570-b6d0-b4191501d847, abstract = {{We study the time-dependent transmission of entanglement entropy through an out-of-equilibrium model interacting device in a quantum transport set-up. The dynamics is performed via the Kadanoff-Baym equations within many-body perturbation theory. The double occupancy <(n) over cap (R dagger)(n) over cap (R down arrow)>, needed to determine the entanglement entropy, is obtained from the equations of motion of the single-particle Green's function. A remarkable result of our calculations is that <(n) over cap (R dagger)(n) over cap (R down arrow)> can become negative, thus not permitting to evaluate the entanglement entropy. This is a shortcoming of approximate, and yet conserving, many-body self-energies. Among the tested perturbation schemes, the T-matrix approximation stands out for two reasons: it compares well to exact results in the low-density regime and it always provides a non-negative <(n) over cap (R dagger)(n) over cap (R down arrow)> For the second part of this statement, we give an analytical proof. Finally, the transmission of entanglement across the device is diminished by interactions but can be amplified by a current flowing through the system. Copyright (C) EPLA, 2011}}, author = {{Puig von Friesen, Marc and Verdozzi, Claudio and Almbladh, Carl-Olof}}, issn = {{0295-5075}}, language = {{eng}}, number = {{2}}, publisher = {{EDP Sciences}}, series = {{Europhysics Letters}}, title = {{Can we always get the entanglement entropy from the Kadanoff-Baym equations? The case of the T-matrix approximation}}, url = {{http://dx.doi.org/10.1209/0295-5075/95/27005}}, doi = {{10.1209/0295-5075/95/27005}}, volume = {{95}}, year = {{2011}}, }