Eur. Phys. J. B (2018) 91: 119
https://doi.org/10.1140/epjb/e2018-90122-9

Regular Article

Optical properties from time-dependent current-density-functional theory: the case of the alkali metals Na, K, Rb, and Cs^★

¹ Laboratoire de Chimie et Physique Quantiques, Université de Toulouse, CNRS, UPS, and European Theoretical Spectroscopy Facility, Toulouse, France
² Laboratoire de Physique Théorique, Université de Toulouse, CNRS, UPS, and European Theoretical Spectroscopy Facility, Toulouse, France

^a e-mail: pina.romaniello@irsamc.ups-tlse.fr

Received: 2 March 2018
Received in final form: 20 April 2018
Published online: 13 June 2018

Abstract

We present the optical conductivity as well as the electron-energy loss spectra of the alkali metals Na, K, Rb, and Cs calculated within time-dependent current-density functional theory. Our ab initio formulation describes from first principles both the Drude-tail and the interband absorption of these metals as well as the most dominant relativistic effects. We show that by using a recently derived current functional [Berger, Phys. Rev. Lett. 115, 137402 (2015)] we obtain an overall good agreement with experiment at a computational cost that is equivalent to the random-phase approximation. We also highlight the importance of the choice of the exchange-correlation potential of the ground state.