Regular Article

Impact of single particle oscillations on screening of a test charge

¹ Institute for Experimental and Theoretical Physics, Al-Farabi Kazakh National University, 71 Al-Farabi str., 050040 Almaty, Kazakhstan
² Institute of Applied Sciences and IT, 40-48 Shashkin str., 050038 Almaty, Kazakhstan
³ Kazakh-British Technical University, 59 Tole bi str., 050000 Almaty, Kazakhstan

^a e-mail: gabdullin@physics.kz

Received: 6 January 2018
Received in final form: 13 April 2018
Published online: 12 June 2018

Abstract

Screening of a test charge by electrons oscillating in an external alternating electrical (laser) field is analyzed. It is shown that single particle oscillations lead to the creation of an oscillatory pattern of the test charge’s potential at large distances. Analysis has been done by considering and neglecting the contribution of ions on the screening. Impact of the quantum diffraction (non-locality) and of the collisional damping on the test charge’s potential is considered. It is shown that electrons are unable to provide screening of the test charge if the frequency of the induced single particle oscillations larger than the electron-plasma frequency. In the opposite case of low frequencies, the potential of the test charge changes its sign if the screening by ions is neglected.