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Electronic, bonding and elastic properties of the ordered SrTi1−x Zrx O3 alloys: a first principles study M. Tedjani1 · M. Driss‑Khodja1 · A. Boudali1 · T. Ouahrani2,3 · B. Amiri4  Received: 6 July 2020 / Accepted: 15 September 2020 © Springer-Verlag GmbH Germany, part of Springer Nature 2020

Abstract By means of first-principles calculations based on the density functional theory (DFT), we have investigated the structural, elastic, electronic, and bonding properties of three SrTi1−x Zrx O3 alloys. The study shows that the substitution of Ti ion by the Zr one can also be undertaken by a tetragonal structure. However, due to the similar ionic radii between substitute cation, the choice of this super-cell leads to a weak change in both structural and dynamical properties and behave similarly even under different applied strains. Electronic as well as bonding properties are more affected by the substitution due to the rearrangement of the atomic orbitals. The calculations of band gaps depict a possible use of the investigated alloys in many UV device applications. Additionally, we will show that deep insight of bonding properties depicts some difference in ionicity degree between alloys. This trend is due essentially to the change in electron valence resulted in a weak variation of energetic orbitals. Keywords  Ab initio calculation · Band structure · Bonding analysis

1 Introduction To date, the demand for novel technological devices has led to modulating new artificial and unusual environments like interfacing two perovskite oxide in its bulk structure. This task could be experimentally archived by modifying their molecular makeup by means of physical vapor deposition [1–3]. For example, some benchmark studies elaborate such interfaces by increasing the thickness of a LaAlO3 film on the SrTiO3 (STO) substrate [4] or by epitaxially grown the GaTiO3/STO interfaces [5, 6]. Such structures are analogous to the traditional layered materials with a specific sandwiched stacking sequence, called also quantum well (QW) [7]. These materials produce an effective way to control and estimate the available electron energy states rising * B. Amiri [email protected] 1



Université Dr Tahar Moulay de Saıda, B.P. 138, Cité el Nasr, 20000 Saïda, Algeria

2



Ecole supérieure en sciences appliquées, B.P. 164, 13000 Tlemcen, Algeria

3

Laboratoire de Physique Théorique, B.P. 230, 13000 Tlemcen, Algeria

4

Present Address: Laboratory of Semiconductor Devices Physics, Normal Higher School, 08000 Bechar, Algeria



to many useful/novel properties. Due to the fact that when two perovskites are placed together, their interface shows a conducting behavior. In fact, a two-dimensional electron gas (2DEG) is generated in the sense that their electrons acquire considerable mobility, which permits them to move freely within the plane of this interconnection [3]. Recently, [8], a 2DEG has been achieved at the interface between the cubic SrTiO3 (STO) and the orthorhombic SrZrO3 (SZO) perovskites via a modulation doping. Measures on the cond