- Tytuł:
- The Green Function Variational Approximation: Significance of Physical Constraints
- Autorzy:
-
Bieniasz, K.
Berciu, M.
Oleś, A. - Powiązania:
- https://bibliotekanauki.pl/articles/1398655.pdf
- Data publikacji:
- 2016-08
- Wydawca:
- Polska Akademia Nauk. Instytut Fizyki PAN
- Tematy:
-
75.25.Dk
03.65.Ud
75.10.Lp
79.60.-i - Opis:
- We present a calculation of the spectral properties of a single charge doped at a Cu(3d) site of the Cu-F plane in KCuF₃. The problem is treated by generating the equations of motion for the Green function by means of subsequent Dyson expansions and solving the resulting set of equations. This method, dubbed the variational approximation, is both very dependable and flexible, since it is a systematic expansion with precise control over elementary physical processes. It allows for deep insight into the underlying physics of polaron formation as well as for inclusion of many physical constraints, such as excluding crossing diagrams and double occupation constraint, which are not included in the self-consistent Born approximation. Here we examine the role and importance of such constraints by analyzing various spectral functions obtained in second order variational approximation.
- Źródło:
-
Acta Physica Polonica A; 2016, 130, 2; 659-663
0587-4246
1898-794X - Pojawia się w:
- Acta Physica Polonica A
- Dostawca treści:
- Biblioteka Nauki
Artykuł