Stripe phase and its interactions with high-Tc superconductivity and Majorana zero mode
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TDLI Meeting Room N600 (East Wing of Floor 6, North Building)
I will introduce two works related to stripe-like charge order observed by scanning tunneling microscopy (STM). The first one is the discovery of stripe phase in the interfacial superconductor FeSe films grown on SrTiO3 (FeSe/STO). Previously, the role of the STO substrate for the superconductivity enhancement has been widely studied. Instead, we focus on FeSe film itself this time. We found that, due to the enhanced electronic correlation and anisotropy, a unique stripe-like charge order develops. We demonstrate that the monolayer FeSe/STO is in close proximity to the stripe phase, and its superconductivity is further promoted by this electronic instability.
In the second part, I will show our STM study on Majorana zero mode (MZM) in 2M-WS2. We observed MZMs in vortex cores of the material, demonstrating that it is a candidate Fu-Kane topological superconductor. Recently, we realized the spatial tuning of MZM by introducing a surface stripe charge order. We found that the charge order does not destroy the bulk topology, but it can effectively push MZM downward away from the 2M-WS2 surface.
Wei Li is an Associate Professor in the Department of Physics at Tsinghua University. He obtained his BS and PhD degrees from Tsinghua University in 2005 and 2011, respectively. He then moved to Stanford University for postdoctoral research. He joined Tsinghua again in January 2016. He is interested in the study of high-temperature superconductivity and topological superconductivity with scanning probe microscopy and molecular beam epitaxy techniques.
Tencent meeting link: https://meeting.tencent.com/dm/KFR5yj9Bp5AU Meeting ID: 442 182 614, no password
