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ORIGINAL PAPER

First-Principles Calculations of Magnetic Properties and Faraday Rotation of Cr-Doped ZnSe with Vacancy Defects Abderrahim Ait-Raiss 1

&

Fatiha Nabah 1 & Mohammed Aggour 1

Received: 4 December 2019 / Accepted: 18 November 2020 # Springer Science+Business Media, LLC, part of Springer Nature 2020

Abstract Using KKR-CPA method within the spin-polarized density functional theory (DFT) with the local density approximation (LDA), we have performed our calculations on ZnSe compound, doped with chromium atoms, for different concentrations. This is to study the effect of this magnetic impurity on the magnetic properties and Faraday rotation of the studied alloy. We also have investigated the effect of defects, by introducing vacancies in Zn sites. On one hand, we have doped our compound with (0.01; 0.05; 0.1; 0.15; 0.2; 0.25) of chromium atoms; on the other hand, we have introduced (0.01; 0.03; 0.05) of vacancy defects in Zn sites, for each state of chromium doping. We have investigated that there is a magnetism appearing when doping with chromium atoms. In addition, the adding of vacancy defects improves the ferromagnetic state. The density of states (DOS) illustrates the analyzed results. Moreover, the energy of each case has been calculated for both the DLM (disordered local moment) and the ferromagnetic states. Keywords Zn1-x-yCrxVacySe . Magnetic properties . KKR-CPA method . Density functional theory (DFT) . DMS

1 Introduction A lot of research works in spintronics are still interested in studying the diluted magnetic semiconductors (DMS). This is in order to enhance the performance of electronic devices. To get this new kind of material, a part of the host material’s cations is usually substituted by magnetic impurities, which are the transition metals (TM) such as Co, Ni, Fe, and Mn [1–12]. ZnSe compound is a wide band gap semiconductor, which represents a large family of alloys that belongs to the II–VI group. We can conclude from the published works that a lot of studies were focused on the III–V family of semiconductors, such as (Ga,Mn)As, see for example ref. [13] and references therein. But the solubility of 3d transition metals in III–V-based DMS was found to be extremely lower than 7–8% with a Curie temperature up to 160 K, whereas the higher solubility in II–VI DMS and the possibility of controlling the localized spins make them much appreciated for fundamental studies [5, 14]. ZnSe is * Abderrahim Ait-Raiss [email protected] 1

Laboratory of Renewable Energy and Environment, Faculty of Sciences, Ibn Tofail University, Kenitra, Morocco

considered as a semiconductor that is optically active in the visible region and has some potential use in thin-film devices, especially in optoelectronic devices such as light emitters (blue laser diodes), photodetectors, and photovoltaic devices. This is due to its wide band direct gap (2.67 eV) and large bonding energy exciton (21 meV) at room temperature [15]. Thanks to its wide band gap, ZnSe is an efficient inorganic sensitizing shell fo