Time-resolved four-wave-mixing spectroscopy for inner-valence transitions

Time-resolved four-wave-mixing spectroscopy for inner-valence transitions.

Noncollinear four-wave-mixing (FWM) techniques at near-infrared (NIR), visible, and ultraviolet frequencies have been widely used to map vibrational and electronic couplings, typically in complex molecules. However, correlations between spatially localized inner-valence transitions among different sites of a molecule in the extreme ultraviolet (XUV) spectral range have not been observed yet. As...

Picosecond time-resolved four-wave mixing experiments in sodium-seeded flames.

Picosecond four-wave mixing experiments have been used to study collisions in a Na-seeded, premixed, methane-air flame. Population gratings are used to measure Na excited-state quenching collision rates, while polarization gratings are used to measure Na ground-state hyperfine coherence randomizing collision rates and overall Na diffusion rates, even though these processes are slower than the e...

Time-resolved four-wave mixing in InAs/InGaAs quantum-dot amplifiers under electrical injection

Time-resolved Hst Spectroscopy of Four Eclipsing Magnetic Cataclysmic Variables

Time-resolved, multi-epoch, Hubble Space Telescope ultraviolet eclipse spectrophotometry is presented for the magnetic cataclysmic variables (mCVs) V1309 Ori, MN Hya, V2301 Oph, and V1432 Aql. Separation of the eclipse light curves into specific wavebands allows the multiple emission components to be distinguished. Accretion-heated photospheric spots are detected in V1309 Ori and V2301 Oph, ind...

Time-resolved diffusing wave spectroscopy applied to dynamic heterogeneity imaging.

We report what is to our knowledge the first observation of a time-resolved diffusing wave spectroscopy (DWS) signal recorded by transillumination through a thick turbid medium: the DWS signal is measured for a fixed photon transit time, which opens the possibility of improving the spatial resolution. This technique could find biomedical applications, especially in mammography.