STM study of topological nodal-line semimetals with nonsymmorphic symmetry

by Dr Zhen Zhu (Shanghai Jiao Tong University)

Wednesday 17 Jun 2020, 13:30 → 14:30 Asia/Shanghai

ONLINE

Abstract

Non-symmorphic crystals are generating great interest as they are commonly found in quantum materials, like iron-based superconductors, heavy-fermion compounds, and topological semimetals. A new type of surface state, a floating band, was recently discovered in the nodal-line semimetal ZrSiSe, but also exists in many non-symmorphic crystals. Little is known about its physical properties. Here, we employ scanning tunneling microscopy to measure the quasiparticle interference of the floating band state on ZrSiSe (001) surface and discover rotational symmetry breaking interference, healing effect and half-missing-type anomalous Umklapp scattering[1]. Our results may pave a way towards potential new applications of nanoelectronics.

One dimensional electronic system is a versatile platform hosting novel physics, such as charge density wave, SSH topological state and solitons, Tomonaga-Luttinger Liquid etc. Here, we systematically study the surface electronic properties on layered composition-tunable compounds Nb2n+1SinTe4n+2 (n=1–5), which is predicted to be a nodal-line semimetal when n=1 (Nb3SiTe6). We observe 1D chains formed on the surface of the compounds via STM. And the 1D electronic state is developed in the compounds with n≥3. Then, the origin of 1D electronic state is discussed[2]. Our experiment demonstrates a tunable and unidirectional 1D electronic system, which offers a concrete platform for the exploration of intriguing 1D electron physics and will enrich the opportunity for future condensed matter physics, material science and nanotechnology researches.

 

[1] Quasiparticle interference and nonsymmorphic effect on a floating band surface state of ZrSiSe.

Zhen Zhu, Tay-Rong Chang, Cheng-Yi Huang, et.al. Nature Communications. 9, 4153 (2018).

[2] A tunable and unidirectional one-dimensional electronic system Nb2n+1SinTe4n+2. Zhen Zhu, Si Li, Meng Yang, et. al. npj Quantum Materials. 5, 35 (2020).

Biography

2015.9-2020.6    Shanghai Jiao Tong University, Ph. D.

2011.9-2015.7    Lanzhou University, B. S.

Chair

Prof. Chi Ming Yim

Division

Condensed Matter

Other information

Venue: TDLI Meeting Room 200

Here is the Zoom link if you prefer to join us remotely:

Meeting room: https://cernet.zoom.com.cn/j/65821181048