Upgrade of scanning tunneling microscope to enable qPlus operation
Abstract
Two-dimensional materials hold tremendous promise for a range of applications from electronics to photonics. While scanning probe microscopy is ideally suited to studying these materials because they are atomically thin, scanning tunneling microscopy (STM) has some significant drawbacks. STM works by having a tunnel current flow between the microscope tip and the sample yet if the sample is not conducting, or in buried heterostructures this mode of operation is not possible. This becomes particularly difficult in topologically protected materials where often the bulk in insulating and only the edges are conducting. Therefore, another scanning probe method of studying these materials is necessary. Non-contact atomic force microscopy (AFM) can provide atomic resolution images without the need for a conducting substrate. This works by placing a sharp metal tip on the end of one arm of a quartz tuning fork and measuring the deflection of the tip with the tuning fork. The proposed qPlus sensor has the advantage that it works in both AFM and STM modes and can easily switch between them for looking at heterogenous samples. This proposal requests funds to upgrade the PIÕs existing STM system to enable qPlus operation. While the PI has made many important advancements in the understanding of two-dimensional materials with STM, the addition of the qPlus AFM mode will enable a wide range of new materials and electronic properties to be studied leading to the discovery of new physical phenomena.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jul 14, 2022
- Source ID
- W911NF2210171
Entities
People
- Brian J LeRoy
Organizations
- Army Contracting Command
- United States Army
- University of Arizona