Helium-Efficient Cryogenic Microwave Impedance Microscopy for Research on Topological Quantum States
Abstract
The objective of this DURIP award is to implement a helium-efficient cryogenic microwave impedance microscope (MIM) based on a dilution refrigerator platform, which will substantially advance our knowledge on topological phases such as quantum spin Hall state, quantum anomalous Hall state, and Axion insulator state. The MIM is capable of achieving a spatial resolution of 10 ~ 100 nm, which is below one millionth of the free-space wavelength at 1 GHz. The base temperature below 100 mK in the dilution refrigerator is crucial for us to study the spatial distribution of local conductance in these systems. The reliquefier will ensure the efficient usage of helium, a precious natural resource undergoing global supply shortage in the present time. Moreover, with the recondensation of helium, the system will be continuously running without being interrupted by helium transfer, which is desirable for careful studies on topological states at cryogenic temperatures.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 02, 2022
- Accession Number
- AD1190342
Entities
People
- Keji Lai
Organizations
- University of Texas at Austin