INTRINSIC ROOM TEMPERATURE FERROMAGNETISM OF SILICON-DOPED ZnO THIN FILMS

Abstract

We report our study on the magnetic properties of Si-doped ZnO thin films fabricated by pulsed laser deposition technique. The Si-doped ZnO thin films show ferromagnetism at room temperature. The saturation magnetism increases from 0 to 2.4 emu/cc with the increasing of Si concentration up to 2%, and then decreases with further increasing of Si concentration. First-principles calculation demonstrates that the origination of ferromagnetism for Si-doped ZnO system is the two unpaired electrons of Si-2p. These unpaired electrons increase the magnetic moments which are responsible for the increasing ferromagnetism.

High-redshift cosmography: auxiliary variables versus Padé polynomials

“…Hence, possibility that a slightly evolving dark energy contribution can fuel the energy momentum-tensor, alleviating the problems related to the today tiny value 1 of Λ, is still valid. Thus, distinguishing dark energy from Λ and understanding whether the equation of state of the Universe is varying (Chevallier & Polarski 2001;Linder 2003;Padmanabhan 2010;Tsujikawa 2010; Aviles & Cervantes-Cota 2011; Clifton et al 2012;Bamba et al 2012;Luongo & Quevedo 2014a,b;Piedipalumbo et al 2014) have widely prompted the search for model-independent treatments and null-diagnostics (Harrison 1976;Visser 2005;Uzan, Clarkson & Ellis 2008;Clarkson, Bassett & Lu 2008;Zunckel & Clarkson 2008;Sahni, Shafieloo & Starobinsky 2008;Nesseris & Shafieloo 2010;Farooq & Ratra 2013;Busti, Holanda & Clarkson 2013;Aviles et al 2014;Escamilla-Rivera & Capozziello 2019; Escamilla-Rivera, Quintero & Capozziello 2020; Lobo, Mimoso & Visser 2020). Model-independent techniques are constructed to give hints on the correct form of dark energy.…”