Quasiparticle interference observation of the topologically non-trivial drumhead surface state in ZrSiTe

TL;DR

This study uses scanning tunneling microscopy to observe quasiparticle interference in ZrSiTe, revealing the topologically non-trivial drumhead surface state and its unique scattering properties, contrasting with similar materials.

Contribution

First direct observation of the drumhead surface state in ZrSiTe via QPI, highlighting its topological nature and spin-split band scattering mechanisms.

Findings

Detected two scattering signals across the drumhead state.

Resolved the energy-momentum relationship of the drumhead state.

Observed spin-split band scattering across the $ extbf{k} ightarrow - extbf{k}$ process.

Abstract

Drumhead surface states that link together loops of nodal lines arise in Dirac nodal-line semimetals as a consequence of the topologically non-trivial band crossings. We used low-temperature scanning tunneling microscopy and Fourier-transformed scanning tunneling spectroscopy to investigate the quasiparticle interference (QPI) properties of ZrSiTe. Our results show two scattering signals across the drumhead state resolving the energy-momentum relationship through the occupied and unoccupied energy ranges it is predicted to span. Observation of this drumhead state is in contrast to previous studies on ZrSiS and ZrSiSe, where the QPI was dominated by topologically trivial bulk bands and surface states. Furthermore, we observe a near $\mathbf{k} \rightarrow -\mathbf{k}$ scattering process across the $\Gamma$-point, enabled by scattering between the spin-split drumhead bands in this material.