Cryogenic Microwave Impedance Microscope with Pulsed Laser Stimulation for Studying Phase Transitions
Abstract
The objective of this DURIP award is to develop a cryogenic microwave impedance microscope (MIM) with broadband and pulsed laser illumination for the study of phase transitions. Different from the thermally driven phase transitions, the photo-induced phase transition illustrated in Fig. 1 is initiated by the photo-excited carriers that redirect the system to a new stable or metastable phase. Owing to the intricate interplay among disorders, electron-electron interactions, and competing orders, electronic inhomogeneity with different spatial configurations is ubiquitously observed in semiconductors, complex oxides and other functional materials. Before our work, however, mesoscopic phase separation has not been addressed for the light-driven phase transitions observed in advanced materials. It is our goal to combine the MIM with nanoscale imaging capability and laser excitation to study the microscopic details of these processes.This program is the continuation of a prior DURIP Grant # W911NF-16-1-0276, which allowed the PI to obtain an optical table, cryogenic stepping/scanning stages, and MIM electronics. With the current support, we have acquired the remainder of the setup, including a professional scanning probe microscopy controller, a number of CW and pulsed lasers, a white-light source, and various optical components. The system is now fully up and running in the PIs laboratory.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 14, 2018
- Accession Number
- AD1072038
Entities
People
- Keji Lai
Organizations
- University of Texas at Austin