Dynamical Cluster Approximation: Cluster Extension of CPA for Disordered System

ORAL

Abstract

The dynamical mean-field approximation (DMFA) or the coherent potential approximation (CPA) provides a convenient and effective method for studying disordered systems; however, non-local short range correlations of the disorder potential are neglected leading to a self-consistent single-site approximation. We combine the recently developed first principles method of Wei Ku and co-workers for the simulation of disordered systems with the dynamical cluster approximation (DCA) to develop a highly efficient means to treat disordered systems. We solve this model system using the DCA, which systematically incorporates short-range nonlocal correlations to the CPA. We apply this method to a number of model systems to illustrate where the DCA or a finite size simulation is more appropriate.

*Work at LSU was funded in part by the National Science Foundation Award Number: EPS 1003897. Work at BNL is supported by the Department of Energy (DOE) CMSN

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Authors

  • Chinedu Ekuma

    • Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA 70803, USA
    • Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA

  • Wei Ku

    • Brookhaven National Laboratory/ Stony Brook University
    • Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York, 11973, USA
    • Brookhaven National Laboratory
    • CMPMSD, Brookhaven National Laboratory

  • Tom Berlijn

    • Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York, 11973, USA
    • Brookhaven National Laboratory

  • Juana Moreno

    • Department of Physics and Astronomy, Louisiana State University, Baton Rouge, Louisiana 70803, USA
    • Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA 70803, USA
    • Louisiana State University
    • Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA
    • Department of Physics and Astronomy, Louisiana State University
    • Department of Physics \& Astronomy, Louisiana State University

  • Mark Jarrell

    • Department of Physics and Astronomy, Louisiana State University, Baton Rouge, Louisiana 70803, USA
    • Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA 70803, USA
    • Louisiana State University
    • Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA
    • Louisiana State University (LSU)
    • Department of Physics and Astronomy, Louisiana State University
    • Department of Physics \& Astronomy, Louisiana State University