Crystal structure and magnetic properties of disordered alloy ErGa3-xMnx

ErGa3-xMnx disordered alloy is successfully prepared by the vacuum arc melting technology,and the crystal structure and magnetic properties are investigated by using the x-ray diffraction and magnetic measurements.The Rietveld structural analysis indicates that the ErGa3-xMnx crystallizes into a cubic structure with space group of Pm3m in Mn doping range of x=0-0.1.However,the disordered alloy with structural formula of Er0.8Ga2^Ⅰ(Ga^Ⅱ,Mn)0.4 as the second phase is separated from cubic phase for the samples with x=0.2 and 0.3,which is induced by substituting the(Ga^Ⅱ,Mn)-(Ga^Ⅱ,Mn)pair at 2e crystal position for the rare earth Er at 1 a site.The lattice parameters tend to increase with Mn content increasing due to the size effect at Ga(1.30A)site by substituting Mn(1.40A)for Ga.The paramagnetic characteristic is observed by doping Mn into ErGa3 at room temperature.With Mn content increasing from x=0 to 0.1,the magnetic susceptibilityχtends to increase.This phenomenon can be due to the increase of effective potential induced by doping Mn into ErGa3.However,the magnetic susceptibilityχcontinues to decrease with the increase of Mn content in a range of x>0.2,which is due to the phase separation from the cubic Er(Ga,Mn)3 to the hexagonal Er0.8Ga2(Ga,Mn)0.4.

A review on 3d transition metal dilute magnetic REIn_(3) intermetallic compounds

The dilute magnetic intermetallic compound(DMIC) is an extended study of the dilute magnetic semiconductor. The giant magnetic effect and room temperature ferromagnetism are induced by doping minor 3d transition metal into REIn_(3) intermetallic compound. Owing to the metallic processability, the REIn_(3)-based DMIC might have the potential application as magnetoelectric device. In this review, the structural stability, magnetic and electric transport properties of REIn_(3-x)T_(x)(RE = rare earth;T = Co, Mn, Fe;x = 0–0.3) have been systematically summarized and analyzed.

Effect of Sm doping into CuInTe_(2) on cohesive energy before and after light absorption

The effects of Sm doping into CuInTe_(2) chalcopyrite on the cohesive energy before and after light absorption are systematically investigated by the empirical electron theory(EET) of solids and molecules.The results show that the static energy of CuIn_(1-x)Sm_(x)Te_(2) decreases with Sm content increasing due to the valence electronic structure modulated by doping Sm into CuIn_(1-x)Sm_(x)Te_(2).The calculated optical absorption transition energy from the static state to the excited energy level in CuIn_(1-x)Sm_(x)Te_(2) accords well with the experimental absorption bandgap of CuIn_(1-x)Sm_(x)Te_(2).Moreover,it is found that the energy bandgap of CuIn_(1-x)Sm_(x)Te_(2) is significantly widened with Sm content increasing due to its special valent electron structure,which is favorable for enhancing the light absorption in a wider range and also for the potential applications in solar cells.

Crystal structure and electromagnetic responses of tetragonal GdAlGe

The ternary rare-earth aluminum germanide GdAlGe with tetragonal structure is systematically studied by x-ray diffraction,magnetic and electric measurements.The magnetic and electric properties of GdAlGe are strongly related to its special magnetic structure formed by magnetic Gd3 isosceles triangles△s.The GdAlGe orders ferromagnetically at 21 K due to the exchanging interaction of Gd3△↑-△↑Gd3.The mechanism of magnetic transport originates from the slip scattering induced by Stoner spin fluctuation in the magnetic ordering region and the spin wave scattering induced by the thermal photon excitation and phonon scattering in the paramagnetic region.The positive magnetoresistance is observed in GdAlGe,which might be due to the disordered magnetic scatter induced by magnetic anisotropy in GdAlGe.