UVA HOME  |  CONTACT US  |  MAP
 
Support UVa's Physics Department! >>
Click here for a printable version of this page.

Condensed Matter Seminars

ics Condensed Matter
Monday, January 26, 2004
3:30 PM
Physics Building, Room 204
Note special date.
Note special time.
Note special room.
Adam Durst [Host: Paul Fendley]
Yale University
"Radiation-Induced Magnetoresistance Oscillations in a 2D Electron Gas"
ABSTRACT:
Recent measurements of a 2D electron gas subjected to microwave radiation reveal a magnetoresistance with an oscillatory dependence on the ratio of radiation frequency to cyclotron frequency. Oscillations grow with radiation intensity, with the minima saturating at zero resistance. We have performed a diagrammatic calculation which yields radiation-induced resistivity oscillations with the correct period and phase. Results are understood via a simple picture of photoexcited disorder-scattered electrons contributing to the dc conductivity. Sufficient intensity drives the calculated minima to negative resistivity, a situation shown by Andreev, Aleiner, and Millis to be unstable to the development of an inhomogeneous current distribution with zero resistivity. Hence, our result, taken together with theirs, provides an explanation for the experiments.

To add a speaker, send an email to phys-speakers@Virginia.EDU. Please include the seminar type (e.g. Condensed Matter Seminars), date, name of the speaker, title of talk, and an abstract (if available).