Research

STM enables the precise placement of individual atoms or molecules on surfaces, enabling the fabrication of artificial lattices and quantum dots with tailored properties. By analyzing tunneling conductance (dI/dV), STM provides direct access to the local electronic states of these systems, revealing quantum behaviors like bonding/antibonding states, topological edge states, and spin textures.

STM INSTRUMENTATION PAPER:

"Design of a scanning tunneling microscope integrated with a glove box for measuring two-dimensional material flakes" Measurement Science and Technology (2025)

"A Modular Design for Ultra-High Vacuum Millikelvin STM Systems" Review of Scientific Instruments (2020)

STM provides atomic-scale access to the strongly correlated electronic states, such as Charge density waves, Correlated insulating states, and Mott Physics, that emerge in 2D systems, where reduced dimensionality enhances interaction effects. The charge tunability in our STM setup enables in-situ exploration of diverse electronic phases within heterostructured 2D materials.

RESEARCH PAPER:

"Electronic Cascades and Chern Insulators in Twisted Bilayer Graphene" Nature (2020)

"Direct observation of multiband charge density waves in NbTe2" Physical Review B (2022)

"Reshaped Weyl fermionic dispersions driven by Coulomb interactions in MoTe2" Physical Review B (2022)

"Zero-bias anomaly and role of electronic correlations in a disordered metal film" New Journal of Physics (2020)

Topological characteristics of materials such as topological insulators, Dirac semimetals, Weyl semimetals, and nodal-line semimetals can be elucidated through quasiparticle interference (QPI) imaging and Landau-level spectroscopy. These techniques reveal non-trivial charge scattering and screening effects, which serve as direct manifestations of the underlying Berry curvature.

RESEARCH PAPER:

"Direct Observation of Anisotropic Coulomb Interaction in a Topological Nodal Line Semimetal" Advanced Science (2025)

"Symmetry dictated grain boundary state in a two-dimensional topological insulator" Nano Letters (2020)

"Higher-order topology in bismuth" Nature Physics (2018)

"Landau quantization and quasiparticle interference in the three-dimensional Dirac semimetal Cd3As2" Nature Materials (2014)

"One-dimensional topological edge states of bismuth bilayers" Nature Physics (2014)

REVIEW PAPER:

"Resolving exotic quantum states using scanning tunneling microscopy" Current Applied Physics (2024)

"Imaging electronic states on topological semimetals using scanning tunneling microscopy" New Journal of Physics (2016)

Topological superconductors host exotic quasiparticles called Majorana zero modes (MZMs), which are predicted to exhibit non-Abelian statistics—a key ingredient for fault-tolerant quantum computing. STM is a powerful technique for elucidating the local electronic structure of MZMs, which is identified through zero-bias conductance peaks (ZBCPs) observed at the ends of 1D topological superconductors or within the vortex cores of 2D topological superconductors under a magnetic field.

RESEARCH PAPER:

"Observation of a Majorana zero mode in a topologically protected edge channel" Science (2019)

"Majorana spin in magnetic atomic chain systems" Physical Review B (2018)

"Distinguishing a Majorana zero mode using spin-resolved measurements" Science (2017)

"High-resolution studies of the Majorana atomic chain platform" Nature Physics (2017)

"Observation of Majorana fermions in ferromagnetic atomic chains on a superconductor" Science (2014)