In contrast to fluorescent lamps and high-power sodium lamps, the use of light-emitting diode (LED) enables control not only photosynthetic photon flux density (PPFD) at plant level, but also relative spectral distribution (RSPD) light because variety, even different times day, producible emitted by LEDs types. Effects on growth morphology have been investigated using several types species. How...

We demonstrate the effective removal of intrinsic distinguishability between entangled-photon pairs in femtosecond spontaneous parametric down-conversion. High-visibility quantum interference is recovered (an increase to 96% from 17%) while preserving the high photon-flux density associated with the use of long nonlinear crystals. This new technique is expected to serve as a basic component in ...

The effect of photosynthetic photon flux density (PPFD) on photosynthetic response (A) to CO(2) partial pressures between 35 pascals and CO(2) compensation point (Gamma) was investigated, especially below PPFD saturation. Spinacia oleracea cv ;Atlanta,' Glycine max cv ;Clark,' and Arbutus unedo were studied in detail. The initial slope of the photosynthetic response to CO(2) ( partial different...

Recent progress in femtosecond (fs) tera-watt (TW) laser development has raised a new fundamental question in atomic and molecular physics, i.e., how atoms and molecules react against an intense electromagnetic field. As is well known, an atom exposed to photons of relatively low flux density is ionized only if the photon energy exceeds the ionization potential of the atom. On the other hand, w...

The rate of absorption of entangled photon pairs is linear in the photon-flux density. We demonstrate that the two-photon absorption cross section is a nonmonotonic function of the entanglement time; it vanishes for certain energy-level configurations and values of the entanglement time. This entanglement-induced two-photon transparency arises from the coherent summation of transition-amplitude...

Suitable detection systems that are capable of recording high photon count rates with single-photon detection are instrumental for coherent X-ray imaging. The new single-photon-counting pixel detector ‘Lambda’ has been tested in a ptychographic imaging experiment on solar-cell nanowires using Kirkpatrick– Baez-focused 13.8 keV X-rays. Taking advantage of the high count rate of the Lambda and dy...