thin films and other topological materials.*

Using electron beam lithography (EBL) and other nano-fabrication techniques, we construct a micro device to be used in conjunction with a Quantum Design Physical Property Measurement System (PPMS) to observe and measure thermal transport properties of monoclinic tungsten disulfide (2M-WS₂) thin films as well as other thin film topological materials.

 

Thermal transport property measurements, and more specifically thermal Hall measurements, are methods of determining topological superconductivity. In topological superconducting materials, it is theorized that Majorana particles exist on the surfaces or edges of the materials which could be observed through the thermal Hall measurements we obtain with this device.

 

This device was fabricated on a silicon substrate using EBL. It contains a resistive heater, a heat sink, and three platinum thermometers to measure both the longitudinal and transverse temperature gradients across the thin film samples. The resistive heater provides heat while the lithium fluoride (LiF) heat sink allows us to maintain a temperature gradient. From here, an out of plane magnetic field is applied to the system to generate the thermal Hall effect where potential Majorana particles will exhibit unique behavior in the thermal conductivity and thermal Hall measurements. We also plan to use this device to study Josephson Junction samples as well as other thin film topological materials.