Near-field Microwave Imaging of Electrostatically Modulated Quantum Materials

Lai, Keji

Title:

Near-field Microwave Imaging of Electrostatically Modulated Quantum Materials

dc.contributor.author	Lai, Keji
dc.contributor.corporatename	Georgia Institute of Technology. School of Physics	en_US
dc.contributor.corporatename	University of Texas at Austin. Dept. of Physics	en_US
dc.date.accessioned	2016-09-07T14:53:11Z
dc.date.available	2016-09-07T14:53:11Z
dc.date.issued	2016-08-29
dc.description	Presented on August 29, 2016 at 6:00 p.m. in the Instructional Center, room 105.	en_US
dc.description	Keji Lai is an Assistant Professor in the Department of Physics at the University of Texas at Austin.
dc.description	Runtime: 60:16 minutes
dc.description.abstract	Field-effect transistors (FETs) are the backbone of modern semiconductor devices. The same concept of electrostatic modulation of carrier densities has also been very fruitful for the exploration of electronic properties in advanced quantum materials. Using a non-invasive microwave impedance microscope with ~100nm resolution and ~1nS sensitivity, we have visualized the metal-insulator transitions of various materials in the FET configuration. The images acquired at different gate voltages of MoS2 and HgTe devices clearly show the spatial evolution of conductance at the edge and bulk of the sample. Strong electrical inhomogeneity is observed in the MIM images, revealing the fluctuations of disorder potential in the 2D layer. I will also discuss the conductance mapping in ion-gel-gated electric double-layer transistors and 2D devices under laser illumination. The combination of novel FETs and impedance microscopy paves the way to study phase transitions in complex materials induced by electrostatic field effects.	en_US
dc.format.extent	60:16 minutes
dc.identifier.uri	http://hdl.handle.net/1853/55804
dc.identifier.uri	https://mediaspace.gatech.edu/media/lai/1_veroprth
dc.language	English	en_US
dc.language.iso	en_US	en_US
dc.publisher	Georgia Institute of Technology	en_US
dc.relation.ispartofseries	Physics Public Lecture Series
dc.subject	Field-effect transistors	en_US
dc.subject	Semiconductors	en_US
dc.title	Near-field Microwave Imaging of Electrostatically Modulated Quantum Materials	en_US
dc.type	Moving Image
dc.type.genre	Lecture
dspace.entity.type	Publication
local.relation.ispartofseries	School of Physics Public Lecture Series
relation.isSeriesOfPublication	f931f7b7-fef6-4b8f-b8a7-d8b64b5536bd