Prof. Xiaoli Dong [Institute of Physics-CAS, China]

Title: Electronic two-dimensionality and close relationship between spin nematicity and superconductivity in FeSe-based superconductor single crystals synthesized via ions decoration

Time: 10:00 - 11:00 AM, Wednesday, July 27, 2016

Place: Conference Room C206, HPSTAR (Beijing)

Host: Dr. Mahmoud Abdel-Hafiez

Abstract:

We have recently developed the hydrothermal ion-exchange and ion-release methods to synthesize high-quality superconducting single crystals of 11111-type (Li,Fe)OHFeSe and 11-type FeSe, respectively. In the high-Tc (Li0.84Fe0.16)OHFe0.98Se crystals, a common temperature scale (T*=120 K) has been established, below which normal state electronic behaviors are getting highly two-dimensional and the AFM spin fluctuations in the FeSe-layers set in. In the binary FeSe crystals, the spin-nematic order has been discerned by two-fold anisotropy in angular-dependent magnetoresistance (AMR), which is turned on below the characteristic temperature Tsn. Remarkably, a universal linear relationship between Tc and Tsn is observed among various superconducting crystals, indicating that the spin nematicity and the superconductivity in FeSe have a common microscopic origin.

Biography of the Speaker:

Prof. Xiaoli Dong works at Institute of Physics-CAS, with her current research interest in unconventional superconducting materials and their physical properties, especially delicate magnetic properties. Prof. Dong obtained her PhD in 1997 from the Hunan University and Institute of Physics-CAS. She then completed a two-year postdoc at National Lab for Superconductivity, Institute of Physics-CAS. From 2001 to 2004, she worked as a Research Associate at Texas Center for Superconductivity at University of Houston. Prof. Dong’s research activities cover iron-based materials & the crystal growth via ion-decoration, intrinsic superconducting phases at magic dopings in cuprates, delicate magnetic properties in functional materials including protein (bio-compass) and ion-battery material. She has published over 100 papers, including JACS, PRL, Nature, Nature Materials and Nature communications with an H-index of 28.