Summary
The library of two-dimensional (2D) materials has recently grown to include topological insulators and semimetals. Their incorporation in special device geometries may lead to novel quantum electronics with enhanced functionalities. Weyl semimetals, in particular, offer the most robust form of topological protection. Recent results from our group indicate that Weyl nodes should be observable at room temperature in thin molybdenum ditelluride (MoTe2) and are furthermore tunable by changing dimensionality. Weyl nodes correspond to points of bulk band degeneracy and are separated in momentum space. In this joint project with Dr. Andrea Damascelli’s group at the University of British Columbia (UBC), we utilize micro-angle-resolved photoemission spectroscopy (micro-ARPES) to image in momentum space the Weyl nodes and surface arcs of MoTe2 and further investigate changes induced by lower dimensionality. Once the Weyl nodes are mapped, we perform transport measurements and utilize scanning photocurrent microscopy to image novel photogalvanic effects induced by the Weyl points in real space. We expect this project will pave the way for future materials exploration and device development that exploits the unique properties of 2D materials through combined ARPES and nanoscale device transport studies.

Figure 1. Sample device geometry. MoTe2 flakes of various thicknesses are transferred on prepatterned gold electrodes deposited on a hexagonal boron nitride (BN)/graphite (Gr) heterostructure and capped with single-layer hBN. The bottom layers provide an ultra-flat substrate for the MoTe2.
Related Content

Metasurfaces for high-efficiency parametric downconversion and complex quantum state generation
Summary Entangled photon sources are crucial for quantum computing, quantum sensing, and quantum communication. Of growing importance are sources relying on spontaneous parametric downconversion (SPDC). Unfortunately, these sources of entangled photons are often constrained by momentum conservation laws. To overcome this limitation and expand the possibility of quantum state engineering, we intend to use metasurfaces […]
February 1, 2023

Repurposing potential drug candidates for the treatment of COVID-19
Summary The main protease (Mpro) in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus responsible for the coronavirus disease (COVID-19), has emerged as a promising drug target. The scientific community has produced a large number of crystallographic structures of the protease, which mediates viral replication and transcription. These structures report several fragments with varied chemotypes […]
May 6, 2020

Engineering and Characterizing Programmable Interaction Graphs in a Trapped Ion Quantum Simulator
Summary Quantum simulators have the potential to bring unprecedented capabilities in areas such as the discovery of new materials and drugs. Engineering precise and programmable interaction graphs between qubits or spins forms the backbone of simulator applications. The trapped ion system is unique in that the interaction graph between qubits can be programmed, in […]
July 24, 2018

Spin Generation and High-Frequency Detection via the Quantum Nonlinear Anomalous Hall Effect in Weyl Semimetals
In magnetic conductors, the passage of current yields an electric field in the transverse direction even without an external magnetic field – this is known as the anomalous Hall effect (AHE). This effect can act as a convenient probe of spin ordering, magnetic textures, spin-orbit coupling, and band topology in solids, and can be further […]
April 19, 2023