• A Ramakanth

      Articles written in Bulletin of Materials Science

    • Dielectric function for the Anderson model

      A Ramakanth

      More Details Abstract Fulltext PDF

      In recent years the study of alloys and compounds containing rare-earth and actinide elements is receiving increasing attention. The Anderson model is most popularly used for studying the theory of these systems. As it displays a large number of anomalous characters in magnetic and electrical properties, it was felt worthwhile to study the dielectric properties of this model. Using the linear response theory of Kubo, the energy and wave vector-dependent dielectric function$$\varepsilon \left( {\bar q,E} \right)$$ is related to the retarded Green’s function of Fourier components of electron density fluctuations$$\left\langle {\left\langle {\rho _{\bar q} ;\rho _{ - \bar q} } \right\rangle } \right\rangle $$. Thus a many-body calculation of$$\varepsilon \left( {\bar q,E} \right)$$ requires the calculation of$$\left\langle {\left\langle {\rho _{\bar q} ;\rho _{ - \bar q} } \right\rangle } \right\rangle $$. The Greens function is calculated using the equation-of-motion method with RPA decoupling. Further, since certain ensemble averages are required as inputs to the calculation, the relevant single-particle Green’s functions are also evaluated.

  • Bulletin of Materials Science | News

    • Editorial Note on Continuous Article Publication

      Posted on July 25, 2019

      Click here for Editorial Note on CAP Mode

© 2017-2019 Indian Academy of Sciences, Bengaluru.