Preferences help
enabled [disable] Abstract
Number of results
2016 | 130 | 2 | 659-663
Article title

The Green Function Variational Approximation: Significance of Physical Constraints

Title variants
Languages of publication
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.
Physical description
  • [1] G. Khaliullin, Prog. Theor. Phys. Suppl. 160, 155 (2005), doi: 10.1143/PTPS.160.155
  • [2] A.J.W. Reitsma, L.F. Feiner, A.M. Oleś, New J. Phys. 7, 121 (2005), doi: 10.1088/1367-2630/7/1/121
  • [3] P. Wróbel, A.M. Oleś, Phys. Rev. Lett. 104, 206401 (2010), doi: 10.1103/PhysRevLett.104.206401
  • [4] W. Brzezicki, A.M. Oleś, M. Cuoco, Phys. Rev. X 5, 011037 (2015), doi: 10.1103/PhysRevX.5.011037
  • [5] G. Martínez, P. Horsch, Phys. Rev. B 44, 317 (1991), doi: 10.1103/PhysRevB.44.317
  • [6] S.A. Trugman, Phys. Rev. B 37, 1597 (1988), doi: 10.1103/PhysRevB.37.1597
  • [7] J. van den Brink, P. Horsch, A.M. Oleś, Phys. Rev. Lett. 85, 5174 (2000), doi: 10.1103/PhysRevLett.85.5174
  • [8] M. Daghofer, K. Wohlfeld, A.M. Oleś, E. Arrigoni, P. Horsch, Phys. Rev. Lett. 100, 066403 (2008), doi: 10.1103/PhysRevLett.100.066403
  • [9] L.F. Feiner, A.M. Oleś, Phys. Rev. B 71, 144422 (2005), doi: 10.1103/PhysRevB.72.144422
  • [10] M. Berciu, H. Fehske, Phys. Rev. B 84, 165104 (2011), doi: 10.1103/PhysRevB.84.165104
  • [11] F. Trousselet, M. Berciu, A.M. Oleś, P. Horsch, Phys. Rev. Lett. 111, 037205 (2013), doi: 10.1103/PhysRevLett.111.037205
  • [12] H. Ebrahimnejad, G.A. Sawatzky, M. Berciu, Nat. Phys. 10, 951 (2014), doi: 10.1038/nphys3130
  • [13] K. Bieniasz, A.M. Oleś, Phys. Rev. B 94, 085117 (2016), doi: 10.1103/PhysRevB.94.085117
  • [14] K. Bieniasz, A.M. Oleś, Phys. Rev. B 88, 115132 (2013), doi: 10.1103/PhysRevB.88.115132
  • [14a] K. Bieniasz, A.M. Oleś, Acta Phys. Pol. A 126, A-80 (2014), doi: 10.12693/APhysPolA.126.A-80
  • [15] K. Bieniasz, A.M. Oleś, Acta Phys. Pol. A 127, 269 (2015)9, doi: 10.12693/APhysPolA.127.26
  • [16] L. Cincio, J. Dziarmaga, A.M. Oleś, Phys. Rev. B 82, 104416 (2010), doi: 10.1103/PhysRevB.82.104416
Document Type
Publication order reference
YADDA identifier
JavaScript is turned off in your web browser. Turn it on to take full advantage of this site, then refresh the page.