IQUIST Seminar Series

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The Illinois Quantum Information Science and Technology Center hosts a series of talks about topics related to Quantum Information Sciences in its various forms, including (but not limiting to): Quantum computers, Quantum simulation, Measuring the elusive Majorana fermion, and Photons. Talks will be given by senior researchers as well as students and postdocs. 

Keji Lai

IQUIST Seminar: "Probing Topology and Correlation by Milli-Kelvin Microwave Microscopy", Keji Lai, University of Texas at Austin

Event Type
Seminar/Symposium
Sponsor
IQUIST
Location
190 Engineering Sciences Building, 1101 W Springfield Ave, Urbana, IL 61801
Date
Apr 1, 2025   11:00 - 11:50 am  
Speaker
Keji Lai, Professor, University of Texas at Austin
Contact
Stephanie Gilmore
E-Mail
stephg1@illinois.edu
Views
47

"Probing Topology and Correlation by Milli-Kelvin Microwave Microscopy"

Abstract: Near-field microwave microscopy has been an actively evolving research field in the past few decades. For the study of quantum materials, the technique is usually configured in cryogenic environments such that the thermal energy is comparable to or smaller than the scales of intrinsic quantum mechanical energy in the system. In this work, we implement a dilution-refrigerator-based scanning microwave impedance microscope (MIM) with a base temperature of 100 mK. The vibration noise of our apparatus with tuning-fork feedback control and close-cycled helium recovery is as low as 1 nm. Using this setup, we have demonstrated the imaging of various quantum materials with flat energy bands. For gated monolayer graphene, the MIM can map out the evolution of edge and bulk states around multiple integer filling factors. For H-stack twisted transition-metal dichalcogenides, the MIM can reveal the presence of correlated states at integer fillings of the moire superlattice. Our study establishes an experimental platform for investigating nanoscale quantum phenomena at ultralow temperatures.

To watch online go to the IQUIST youtube channel:   https://www.youtube.com/channel/UCCzAySwQXF8J4kRolUzg2ww

For Zoom link you may check the IQUIST calendar weekly email or contact Stephanie Gilmore (stephg1@illinois.edu). To subscribe to our weekly email for event announcements, please go to https://lists.illinois.edu/lists/subscribe/iquist-announcements.

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