Role of vertex corrections in the matrix formulation of the random phase approximation for the multiorbital Hubbard model

Altmeyer, Michaela; Guterding, Daniel; Hirschfeld, P. J.; Maier, Thomas A.; Valenti, Roser; Scalapino, Douglas J.

doi:10.1103/PhysRevB.94.214515

Title: Role of vertex corrections in the matrix formulation of the random phase approximation for the multiorbital Hubbard model

Abstract

In the framework of a multiorbital Hubbard model description of superconductivity, a matrix formulation of the superconducting pairing interaction that has been widely used is designed to treat spin, charge, and orbital fluctuations within a random phase approximation (RPA). In terms of Feynman diagrams, this takes into account particle-hole ladder and bubble contributions as expected. It turns out, however, that this matrix formulation also generates additional terms which have the diagrammatic structure of vertex corrections. Furthermore we examine these terms and discuss the relationship between the matrix-RPA superconducting pairing interaction and the Feynman diagrams that it sums.

Authors:

Altmeyer, Michaela ^[1]; Guterding, Daniel ^[1]; Hirschfeld, P. J. ^[2];

^[3]; Valenti, Roser ^[1]; Scalapino, Douglas J. ^[4]

Goethe-Univ. Frankfurt, Frankfurt am Main (Germany)
Univ. of Florida, Gainesville, FL (United States)
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Univ. of California, Santa Barbara, CA (United States)

Publication Date:: Wed Dec 21 00:00:00 EST 2016

Research Org.:: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

Sponsoring Org.:: USDOE Office of Science (SC)

OSTI Identifier:: 1399530

Alternate Identifier(s):: OSTI ID: 1336968

Grant/Contract Number:: AC05-00OR22725; FG02-05ER46236

Resource Type:: Accepted Manuscript

Journal Name:: Physical Review B

Additional Journal Information:: Journal Volume: 94; Journal Issue: 21; Journal ID: ISSN 2469-9950

Publisher:: American Physical Society (APS)

Country of Publication:: United States

Language:: English

Subject:: 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY

Citation Formats


                    Altmeyer, Michaela, Guterding, Daniel, Hirschfeld, P. J., Maier, Thomas A., Valenti, Roser, and Scalapino, Douglas J. Role of vertex corrections in the matrix formulation of the random phase approximation for the multiorbital Hubbard model.  United States: N. p., 2016. 
Web.  doi:10.1103/PhysRevB.94.214515.

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                    Altmeyer, Michaela, Guterding, Daniel, Hirschfeld, P. J., Maier, Thomas A., Valenti, Roser, & Scalapino, Douglas J. Role of vertex corrections in the matrix formulation of the random phase approximation for the multiorbital Hubbard model.  United States.  https://doi.org/10.1103/PhysRevB.94.214515

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                    Altmeyer, Michaela, Guterding, Daniel, Hirschfeld, P. J., Maier, Thomas A., Valenti, Roser, and Scalapino, Douglas J. Wed .  
"Role of vertex corrections in the matrix formulation of the random phase approximation for the multiorbital Hubbard model".  United States.  https://doi.org/10.1103/PhysRevB.94.214515.  https://www.osti.gov/servlets/purl/1399530.

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@article{osti_1399530,

  title        = {Role of vertex corrections in the matrix formulation of the random phase approximation for the multiorbital Hubbard model},

  author       = {Altmeyer, Michaela and Guterding, Daniel and Hirschfeld, P. J. and Maier, Thomas A. and Valenti, Roser and Scalapino, Douglas J.},

  abstractNote = {In the framework of a multiorbital Hubbard model description of superconductivity, a matrix formulation of the superconducting pairing interaction that has been widely used is designed to treat spin, charge, and orbital fluctuations within a random phase approximation (RPA). In terms of Feynman diagrams, this takes into account particle-hole ladder and bubble contributions as expected. It turns out, however, that this matrix formulation also generates additional terms which have the diagrammatic structure of vertex corrections. Furthermore we examine these terms and discuss the relationship between the matrix-RPA superconducting pairing interaction and the Feynman diagrams that it sums.},

  doi          = {10.1103/PhysRevB.94.214515},

  journal      = {Physical Review B},

  number       = 21,

  volume       = 94,

  place        = {United States},

  year         = {Wed Dec 21 00:00:00 EST 2016},

  month        = {Wed Dec 21 00:00:00 EST 2016}

}

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Works referencing / citing this record:

Orbital selective pairing and gap structures of iron-based superconductors
journal, May 2017

Kreisel, Andreas; Andersen, Brian M.; Sprau, P. O.
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Title: Role of vertex corrections in the matrix formulation of the random phase approximation for the multiorbital Hubbard model

Abstract

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