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

Magnetoelectric Coupling in New Composite Multiferroic Nanostructures as High-Density Quantum Multistate Memory Elements
Summary Magnetoelectric multiferroics are materials that exhibit correlated ferroelectric and ferromagnetic properties (i.e., a magnetoelectric effect). The resulting ability of these materials to simultaneously store data in electric polarization and magnetic moment could increase data storage density and data processing speed while reducing energy consumption. This project aims to design and fabricate new composite multiferroic […]
February 1, 2023

Hybrid Quantum Repeater based on Atomic Quantum Memories and Telecom Wavelength Entangled Photon-Pairs Generated from Semiconductor Nanowires
Summary Losses in physical channels, such as optical fibres, limit existing quantum communication systems to modest distance ranges. Since amplification of quantum signals is fundamentally not possible, we look to extend the range and functionality of these quantum channels by adding quantum memory nodes that can daisy-chain multiple lengths of quantum channels through entanglement […]
October 29, 2018

On-Chip Microwave-Optical Quantum Interface
Summary In this project we develop a quantum interface between microwave and optical photons as a key enabling technology of a hybrid quantum network. In such a network, the robust optical photons carry quantum information through optical fibres over long distances, while superconducting microwave circuits protected from thermal photon noise by the low temperature […]
October 29, 2018
Spin-transfer Torque Magnetic Random Access Memory for On-chip Spin Information Storage
Summary Leakage power in semiconductor memories, such as Dynamic Random Access Memory (DRAM) and Static Random Access Memory (SRAM), can be substantial and is one of the limits for scalability of classical electronics. This is attributed to the fact that the information stored is volatile, requiring constant refreshing, as well as reprogramming upon powering […]
August 6, 2018