title: Three-dimensional electronic spectroscopy of excitons in GaAs quantum wells.
abstract: We demonstrate three-dimensional (3D) electronic Fourier transform spectroscopy of GaAs quantum wells using four fully phase-coherent, noncollinear optical fields. Since the full complex signal field is measured as a function of all three time intervals, nearly every peak in the resulting 3D spectral solid arises from a distinguishable sequence of transitions represented by a single Feynman pathway. We use the 3D spectral peaks to separate two pathways involving weakly bound mixed biexcitons generated in different time orders. In the process, we reveal a peak that was previously obscured by a correlated but unbound exciton pair coherence. We also demonstrate a calibration procedure for the carrier frequency which yields biexciton binding energy values with high accuracy.
authors.affiliation: Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
authors.forename: Daniel B
authors.initials: DB
authors.lastname: Turner
authors.forename: Katherine W
authors.initials: KW
authors.lastname: Stone
authors.forename: Kenan
authors.initials: K
authors.lastname: Gundogdu
authors.forename: Keith A
authors.initials: KA
authors.lastname: Nelson