Diagrammatic Expansion for Positive Spectral Functions in the Steady-State Limit
Abstrakti
Recently, a method was presented for constructing self‐energies within many‐body perturbation theory that is guaranteed to produce a positive spectral function for equilibrium systems, by representing the self‐energy as a product of half‐diagrams on the forward and backward branches of the Keldysh contour [Phys. Rev. B 2014, 90, 115134]. An alternative half‐diagram representation that is based on products of retarded diagrams is derived here. This approach extends the method to systems out of equilibrium. When a steady‐state limit exists, it is shown that our approach yields a positive definite spectral function in the frequency domain.
Päätekijät
Aineistotyyppi
Artikkelit
Tutkimusartikkeli
Julkaistu
2019
Sarja
Aiheet
Julkaisu tutkimustietojärjestelmässä
Julkaisija
Wiley - VCH Verlag GmbH & Co. KGaA
Julkaisun pysyvä osoite
https://urn.fi/URN:NBN:fi:jyu-202001081106Käytä tätä linkitykseen
Vertaisarvioinnin tila
Vertaisarvioitu
ISSN
0370-1972
DOI
https://doi.org/10.1002/pssb.201800615
Kieli
englanti
Julkaisussa
Physica Status Solidi. B: Basic Research
Viite
- Hyrkäs, M., Karlsson, D., & van Leeuwen, R. (2019). Diagrammatic Expansion for Positive Spectral Functions in the Steady-State Limit. Physica Status Solidi. B: Basic Research, 256(7), 1800615. https://doi.org/10.1002/pssb.201800615
Lisenssi
Funder(s)
Suomen Akatemia
Suomen Akatemia
Funding program(s)
Tutkijatohtori, SA
Akatemiahanke, SA
Postdoctoral Researcher, AoF
Academy Project, AoF
Lisätietoja rahoituksesta
D.K. acknowledges the Academy of Finland for funding under Project No. 308697. M.H. thanks the Finnish Cultural Foundation for support. R.v.L. acknowledges the Academy of Finland for funding under Project No. 317139.
Copyright© 2019 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim