Persistent exciton-type many-body interactions in GaAs quantum wells measured using two-dimensional optical spectroscopy

Studies have shown that many-body interactions among semiconductor excitons can produce distinct features in two-dimensional optical spectra. However, to the best of our knowledge, the dynamics of many-body interactions have not been measured in two-dimensional (2D) spectroscopy studies. Here we mea...

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Bibliographic Details
Main Authors: Turner, Daniel B., Wen, Patrick, Arias, Dylan H., Nelson, Keith Adam, Li, Hebin, Moody, Galan, Siemens, Mark E., Cundiff, Steven T.
Other Authors: Massachusetts Institute of Technology. Department of Chemistry
Format: Article
Language:en_US
Published: American Physical Society 2012
Online Access:http://hdl.handle.net/1721.1/71685
https://orcid.org/0000-0003-2358-6967
https://orcid.org/0000-0001-7804-5418
Description
Summary:Studies have shown that many-body interactions among semiconductor excitons can produce distinct features in two-dimensional optical spectra. However, to the best of our knowledge, the dynamics of many-body interactions have not been measured in two-dimensional (2D) spectroscopy studies. Here we measure 2D spectra of GaAs quantum wells at many different “waiting” times and study the time dependence of the spectral features. Characteristic signatures of exciton polarization correlations manifest in the diagonal peaks decay at the exciton dephasing rate, consistent with theoretical predictions. Other many-body interactions manifest in off-diagonal features decay much more slowly. These persistent off-diagonal features must be due to many-body interactions involving exciton populations, and their persistence cannot be predicted by theoretical descriptions restricted to the coherent limit.