Chenyi Shen

Ba2Ti2Fe2As4O: A New Superconductor Containing Fe2As2 Layers and Ti2O Sheets

We have synthesized a new oxypnictide, Ba2Ti2Fe2As4O, via a solid-state reaction under a vacuum. The compound crystallizes in a body-centered tetragonal lattice, which can be viewed as an intergrowth of BaFe2As2 and BaTi2As2O, thus containing Fe2As2 layers and Ti2O sheets. Bulk superconductivity at 21 K is observed after annealing the as-prepared sample at 773 K for 40 h. In addition, an anomaly in resistivity and magnetic susceptibility around 125 K is revealed, suggesting a charge- or spin-density wave transition in the Ti sublattice.

Sr and Mn co-doped LaCuSO: A wide band gap oxide diluted magnetic semiconductor with TC around 200 K

Here we report the synthesis of a bulk oxide diluted magnetic semiconductor (DMS) system La1−xSrxCu0.925Mn0.075SO (x = 0, 0.025, 0.05, 0.075, and 0.1). As a wide band gap p-type oxide semiconductor, LaCuSO satisfies all the conditions forecasted theoretically to be a room temperature DMS. The Curie temperature (TC) is around 200 K as x ≥ 0.05, which is among the highest TC record of known bulk DMS materials up to now. The system provides a rare example of oxide DMS system with p-type conduction, which is important for formation of high temperature spintronic devices.

Li2RhO3: A spin-glassy relativistic Mott insulator

Motivated by the rich interplay among electronic correlation, spin-orbit coupling (SOC), crystal-field splitting, and geometric frustrations in the honeycomb-like lattice, we systematically investigated the electronic and magnetic properties of Li

Weakly ferromagnetic metallic state in heavily doped Ba1−xKxMn2As2

_2

Magnetism and crystalline electric field effect in ThCr2Si2-type CeNi2As2

RhO

Pd site doping effect on superconductivity in Nb2Pd0.76S5

_3

Variable range hopping conductivity and spin glass behavior in spin-ladder Ba0.6K0.4Fe2Se3 single crystals

. The material is semiconducting with a narrow band gap of

Effect of Zn doping in under- and over-doped LaFe1−xCoxAsO system

\Delta\sim

Magnetic phase diagram in the Co-rich side of the L Co 1 − x Fe x AsO ( L = La, Sm) system

78 meV, and its temperature dependence of resistivity conforms to 3D variable range hopping mechanism. No long-range magnetic ordering was found down to 0.5 K, due to the geometric frustrations. Instead, single atomic spin-glass behavior below the spin-freezing temperature (

Two superconducting domes separated by a possible Lifshitz transition in LaFeAs1−xPxO

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