Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE
Advances in optical two-dimensional spectroscopy applied to the study of semiconductor and atomic systems
Alan D. Bristow, Xingcan Dai, D. Karaiskaj, Galan Moody, Steven T. Cundiff
Abstract
Electronic structure and dynamics are captured by optical 2D-Fourier-transform (2DFT) spectroscopy, which tracks the phase of the nonlinear signal during two time delays of a multi-pulse excitation sequence. These Fourier-transformed spectra separate and isolate overlapping and competing contributions to the coherent response. We have developed an ultra-stable platform consisting of nested interferometers with active phase control, allowing for exploration of single- and two-quantum coherences. Phase-resolved spectra are retrieved by all-optical determination of experimental phase ambiguities. GaAs quantum wells show suppression of many-body interactions in cross-linear polarized 2DFT spectra and many-body two-quantum coherences. Potassium vapor also shows unexpected two-quantum coherences.