On the Origin of Magnetic Phase Transitions in Low-Dimensional CaFe4As3

Prof.Rongying Jin
Department of Physics and Astronomy
Louisiana State University, USA

时间：2015年6月19日 星期五 上午 10:00
地点：唐仲英楼 A313

附报告简介：
"On the Origin of Magnetic Phase Transitions in Low-Dimensional CaFe4As3"
Rongying Jin， Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA 70803, USA

Metallic CaFe4As3 consists of FeAs4 building blocks, similar to Fe-based superconductors. The edge-shared FeAs4 tetrahedra form ribbons along the b direction and a rectangular network in the ac plane, making needle-like CaFe4As3 single crystals. Under zero magnetic field, both longitudinal and transverse spin-density waves are formed at TN1 ~ 90 K and TN2 ~ 26 K, respectively. Interestingly, these transitions are insensitive to chemical doping (e.g., Pt or Ga) but susceptible to the application of magnetic field. In addition to the variation of TN1 and TN2, magnetic field induces the third magnetic phase transition due to spin flop, generating a rich magnetic phase diagram. The possible origin of these magnetic phase transitions will be discussed.