Yupeng Li

On the origin of ferromagnetism in CeO2 nanocubes

Magnetic behaviors of pure CeO2 nanoparticles and nanocubes have been investigated both experimentally and theoretically. It is found that monodisperse CeO2 nanocubes with an average size of 5.3 nm do show ferromagnetic behavior at ambient temperature with a saturation magnetization of about 5.7 memu/g and coercive force of about 69 Oe. First-principles calculations reveal that oxygen vacancies in pure CeO2 cause spin polarization of f electrons for Ce ions surrounding oxygen vacancies, resulting in net magnetic moment for pure CeO2 samples. One oxygen vacancy at surface can induce more magnetic moments than those induced by one oxygen vacancy in bulk. The results obtained here provide evidence that pure CeO2 sample with oxygen vacancies can indeed have magnetic behavior. This study will stimulate more investigations for understanding the origin of ferromagnetic TM-doped CeO2 (TM=3d transition metals) in a particular case and TM-doped semiconductor oxides in general at ambient temperature.

Effects of cobalt doping and phase diagrams of LFe1-xCox AsO (L=La and Sm)

Chemical doping has recently become a very important strategy to induce superconductivity especially in complex compounds. Distinguished examples include Ba-doped La

Helicity protected ultrahigh mobility Weyl fermions in NbP

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Effect of selenium doping on the superconductivity of Nb2Pd(S1−xSex)5

CuO

The role of band alignment in p-type conductivity of Na-doped ZnMgO: Polar versus non-polar

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Negative magnetoresistance in Weyl semimetals NbAs and NbP: Intrinsic chiral anomaly and extrinsic effects

(the first high temperature superconductor), K-doped BaBiO

Controllable spin-orbit coupling and its influence on the upper critical field in the chemically doped quasi-one-dimensionalNb2PdS5superconductor

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Sr0.9K0.1Zn1.8Mn0.2As2: A ferromagnetic semiconductor with colossal magnetoresistance

, K-doped C

Giant linear magneto-resistance in nonmagnetic PtBi2

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Interaction between two structural blocks and its correlation with superconductivity in SmFeAsO1-xFx and SmFe1-xMxAsO (M=Co,Ni)

and Na