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
Tuning Spin-Exchange Interactions in Low-Dimensional Metal Halide Perovskites: A New Class of Semiconductor Quantum Materials
Summary Leakage current in electronic components is one of the limiting factors for the performance of conventional computers which use charges and currents as physical information carriers. Spintronics offers an alternative by using electron spin for information transfer, processing and storage, enabling the design of non-volatile computer memory and more energy-efficient electronic devices. In this […]
October 1, 2019
Functionalized Nanodiamonds for Sensing Biochemical Processes
Summary Chemotherapy is limited by the failure to clinically monitor the efficacy of the treatment in real-time, which results in suboptimal chemotherapy being given for a prolonged period. Predicting the outcome of chemotherapy immediately after drug administration can increase diagnostic accuracy, efficacy outcomes, and successful treatment. Quantum nanodiamond sensors can be used as optical sensors […]
August 31, 2022
Entangled States of Beams and their Applications
Summary With David Cory and collaborators at the National Institute of Standards and Technology (NIST) we explore how to engineer beams of neutron or photons that carry entanglement. The degrees of freedom that can be entangled include spin (polarization), momentum, displacement, and angular momentum. These have potential applications ranging from studies of helical internal magnetic fields […]
September 7, 2016
Harnessing the Promise of Quantum Materials for Future Electronic Devices
Summary Two-dimensional (2D) quantum materials, such as graphene and molybdenum disulfide, have great potential for use in future flexible and wearable electronics applications. With traditional silicon-based electronics nearing their theoretical performance limits, nano-electronics made from 2D quantum materials offer breakthrough opportunities for energy-efficient, wearable ubiquitous computation. In this project, we will study integration of […]
June 14, 2018