A nonclassical light source is used to demonstrate experimentally the absolute efficiency calibration of a photon-number-resolving detector. The photon-pair detector calibration method developed by Klyshko for single-photon detectors is generalized to take advantage of the higher dynamic range and additional information provided by photon-number-resolving detectors. This enables the use of brig...

Emissions trading is regarded as a crucial instrument for a cost-effective implementation of climate policy. At the same time, the shape of global climate policy after the expiration of the Kyoto Protocol in 2012 is highly uncertain. Intensity targets, which limit the amount of emissions per output, have been proposed as an alternative to Kyotostyle absolute emission targets. In fact, the emerg...

The new high effiency extreme ultraviolet overview spectrometer (HEXOS) system for the stellarator Wendelstein 7-X is now mounted for testing and adjustment at the tokamak experiment for technology oriented research (TEXTOR). One part of the testing phase was the intensity calibration of the two double spectrometers which in total cover a spectral range from 2.5 to 160.0 nm with overlap. This w...

Correlated photons can be used to measure the quantum efficiency of photon counting photodetectors without ties to any externally calibrated standards. We present a study of measurement systematics aimed at reducing the measurement uncertainties to the 0.1% level, and developing a robust measurement protocol.

Triple junction lnGaP/GaAs/Ge solar cells are highly current mismatched due to the excess current generating capability of the germanium subcell. This severe current mismatch invites new approaches for increasing performance beyond that of current triple junctions: Presented here are two approaches for improving the efficiency of III-V multi-junctions beyond that of current triple junction tech...

The organic phosphor p-terphenyl is used as a wavelength-converter coating in some soft-x-ray detectors. We have measured the absolute photoluminescent efficiency of p-terphenyl as a function of incident photon energy from 36 to 191 eV. We have also measured changes in the efficiency caused by soft-x-ray fluence (total photons absorbed per unit area) at several photon energies in this range. We...

H.264 is the latest HDTV video compression standard, which provides a significant improvement in coding efficiency at the cost of huge computation complexity. Provided that discrete cosine transform coefficient(DCT) blocks can be quantized to all zeros, the process of transform and quantization on this all-zero block(AZB) can be skipped, which will reduce significant redundant computations. In ...