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	Quantum Efficiency (Site not responding. Last check: 2007-11-03)
		The "quantum efficiency" (Q.E.) is the ratio of the number of carriers collected by the solar cell to the number of photons of a given energy incident on the solar cell.
		The quantum efficiency may be given either as a function of wavelength or as energy.
		The quantum efficiency can be viewed as the collection probability due the generation profile of a single wavelength, integrated over the device thickness and normalized to the incident number of photons.
	www.udel.edu /igert/pvcdrom/CELLOPER/QUANTUM.HTM (375 words)

	Quantum efficiency - Wikipedia, the free encyclopedia
		Quantum efficiency (QE) is a quantity defined for a photosensitive device such as photographic film or a charge-coupled device (CCD) as the percentage of photons hitting the photoreactive surface that will produce an electron–hole pair.
		The Quantum Efficiency of a solar cell is a very important measure for solar cells as it gives information on the current that a given cell will produce when illuminated by a particular wavelength.
		Both the quantum efficiency and the responsivity are functions of the photons' wavelength.
	en.wikipedia.org /wiki/Quantum_efficiency (380 words)

	Solar Energy Technologies Program: Quantum Efficiency Measurements
		Quantum efficiency (QE) is the ratio of the number of charge carriers collected by the solar cell to the number of photons — or packets of light — of a given energy shining on the solar cell.
		The quantum efficiency ideally has a square shape, where the QE value is fairly constant across the entire spectrum of wavelengths measured.
		In somewhat technical terms, the quantum efficiency can be viewed as the collection probability due to the generation profile of a single wavelength, integrated over the device thickness and normalized to the number of incident photons.
	www1.eere.energy.gov /solar/quantum_efficiency.html?print (404 words)

	Quantum dice debut TRN 011404
		Quantum random numbers could also be useful for increasing the efficiency of quantum secret-sharing schemes, quantum encryption and various forms of quantum communications.
		A quantum particle decoheres, or is knocked out of its quantum state, when it interacts with energy from the environment in the form of light, heat, electricity or magnetism.
		Random quantum operations can be used as control operations that, when subjected to the noise affecting a prototype quantum computer, will generate a response that depends only on the noise, he said.
	www.trnmag.com /Stories/2004/011404/Quantum_dice_debut_011404.html (958 words)

	Olympus Microscopy Resource Center: Digital Imaging in Optical Microscopy - Concepts in Digital Imaging - Electron ...
		Quantum efficiency now exceeds 90 percent and read noise is limited to less than 2 electrons (root-mean-square) in some back-illuminated CCD cameras.
		The efficiency of the impact ionization process, which produces charge gain during electron transfer in the specialized serial register, is inversely dependent on temperature.
		In comparing quantum efficiencies of different detector types, the effect of all loss mechanisms and statistical noise sources must be considered.
	www.olympusmicro.com /primer/digitalimaging/concepts/emccds.html (3619 words)

	First white LED using quantum dots created
		Efficiently extracting all three colors in such a device requires costly chip designs, which likely cannot compete with conventional fluorescent lighting but can be attractive for more specialized lighting applications.
		Quantum dot phosphors are integrated with a commercial LED chip that emits in the near ultraviolet at 400 nanometers by encapsulating the chip with a dot-filled epoxy, creating a dome.
		The quantum dots in the dome absorb the invisible 400 nanometer light from the LED and reemit it in the visible region — a principle similar to that used in fluorescent lighting.
	www.physlink.com /News/071403QuantumDotLED.cfm (1052 words)

	Completed Research \| Solid State Lighting \| Programs \| LRC
		Quantum dots behave like phosphors, but they can be tuned to radiate any color simply by changing the physical size of the dot.
		Quantum dots (QDs) that emit monochromatic light at 520 nm and 620 nm wavelengths were tested to understand their photoluminescence properties and their potential as a down-conversion material for white LEDs.
		Finally, to compare the luminous efficiency and thermal sensitivity of the QDs with that of the YAG:Ce phosphor, samples of both were dissolved in the same type of binding material (epoxy) and placed on microscope slides. The results showed that the efficiency of the QDs was much lower than that of the YAG:Ce phosphor.
	www.lrc.rpi.edu /programs/solidstate/completedProjects.asp?ID=91 (460 words)

	Photonic Quantum Information Systems
		Furthermore, correcting for the quantum efficiency of the detector, a direct observation of oscillations in the photon number distribution was possible.
		Generation of states containing 1,2,3 and 4 photons with high fidelity was experimentally demonstrated, and the effect of the quantum efficiency of the detector on the generation rate and the fidelity of the created states was studied.
		Quantum cryptography or quantum key distribution (QKD), the most advanced technology in the field of quantum information, allows two remote parties to exchange a sequence of random bits and subsequently check their secrecy.
	feynman.stanford.edu /charles.htm (3049 words)

	International Radiation Detectors: UVG: Quantum Yield (Site not responding. Last check: 2007-11-03)
		Recently, 1 cm^2 active area UVG series diodes were used to determine quantum yield (number of electron-hole pairs generated per absorbed photon) of silicon in 254 nm to 160 nm spectral region [1].
		Quantum yield in this region has been determined for the first time and is shown in Fig.
		Owing to their 100% collection efficiency, the external quantum efficiency of UVG-series photodiodes can be calculated in the UV and short wavelength visible (about 160 nm to 600 nm) as the product of the quantum yield times one minus the reflectance of the photodiode.
	www.ird-inc.com /uvgqua.html (225 words)

	Spatial Variations in Quantum Efficiency
		As discussed in section 4.7.1 above, we have measured quantum efficiency (relative to a reference detector) of each ACIS flight device as a function of position.
		Maps showing the spatial uniformity of the relative quantum efficiency at each measurment energy are presented in Figures 4.77-4.86.
		Figure 4.77: Uniformity maps and histograms showing the spatial uniformity of the quantum efficiency of ACIS flight device I0 (w203c4r) relative to reference device w190c3 at seven energies.
	www.astro.psu.edu /xray/docs/cal_report/node116.html (1161 words)

	Basic CCD's
		Quantum efficiency is the number of photoelectrons that are generated in a pixel for every photon of light that hits the surface above it.
		Quantum efficiency is, in simple terms, a percentage of light you detect with your CCD.
		Charge transfer efficiency is how well the photoelectrons from one pixel are transferred to the adjacent pixel during a shift operation.
	wfc3.gsfc.nasa.gov /MARCONI/basic.html (507 words)

	CCD quantum efficiency.
		Having all the absorption coefficients in hand it is possible to calculate the quantum efficiency of the CCD taking into account transmission of all the layers in the gate structure of the frontside CCD.
		4.60 is shown a plot of quantum efficiency as a function of energy for the frontside illuminated device.
		The dashed line in the Figure represents results of the quantum efficiency measurement of the frontside CCD at the SX700 beamline at BESSY.
	space.mit.edu /ACIS/cal_report/node83.html (492 words)

	HRC-S Calibration Data Products
		The absolute quantum efficiency of the central segment of the HRC-S was measured at eight energies, and each wing segment was measured at four.
		The quantum efficiency at the appropriate dispersed location in the +1 and -1 orders as a function of energy is plotted in Figure 3.
		The ratio of the quantum efficiency in the +1 order to the -1 order.This is the ratio at the appropriate dispersed location on the MCP.
	hea-www.harvard.edu /HRC/calib/hrcs_qe.html (1393 words)

	HP Labs : Quantum Science Research : Nanophotonics and Quantum Optics
		Quantum Information Science (QIS) is a rapidly emerging discipline with the potential to revolutionize measurement, computation and communication.
		Similarly, quantum metrology and imaging have interest for the nanoscale manufacturing and physical security industries, as these techniques allow tiny phase shifts, displacements, and forces to be accurately measured remotely even when the target is enclosed within an inaccessible or hostile environment.
		Furthermore, it is already clear that distributed quantum algorithms can efficiently enable solutions to economics problems (e.g., public goods ) that are difficult to treat with conventional mechanisms, but it is not yet known whether other economic procedures — such as resource allocation — have superior quantum solutions.
	www.hpl.hp.com /research/qsr/quantumoptics.html (869 words)

	Quantum Efficiency and Performance of Retinal Ganglion Cells
		Second, the quantum efficiency cannot be determined when the stimulus is a decrement of 100% modulation.
		/Pm A general expression for the efficiency of an arbitrary Poisson box may be obtained by equating d' for an ideal detector handicapped by a Poisson box (equation 3) with d' for an ideal detector handicapped by a filter (equation 14) and solving for F.
		The range of quantum efficiencies for the filter component for the eight cells was 3% to 29% with an average of 14%.
	research.opt.indiana.edu /Library/scoton/scoton.html (4987 words)

	IBM Research \| Projects \| Solid State Quantum Computing
		Since the advent of powerful algorithms for quantum computation, we have been developing theoretical approaches for the physical implementation of these devices.
		We proved that two-qubit interactions are sufficient to implement any quantum algorithm, and introduced some of the initial ideas for what became known as NMR quantum computing.
		We have applied these criteria to develop a specific model for a solid state implementation, in which the qubits are represented by the spins of individual electrons trapped in an array of quantum dots.
	www.research.ibm.com /ss_computing/ss_quantum_comp.html (225 words)

	OLED Exhibits ~10 Percent External Quantum Efficiency (Site not responding. Last check: 2007-11-03)
		They note that the presumed maximum external quantum efficiency of the device was 5 percent, and suggest that the suitability of fluorescent OLEDs for a variety of display and illumination applications should be reconsidered.
		To determine the external quantum efficiency of the OLED, they employed a spectroradiometer from Topcon Corp. of Tokyo, which was connected to a 6-in.-diameter integrating sphere.
		The control device exhibited an external quantum efficiency of approximately 1 percent, leading them to conclude that the higher efficiency of the three-layer OLED was the result of material selection (likely the use of the anthracene derivative DBzA) and not the result of enhanced outcoupling.
	www.photonics.com /content/spectra/2006/October/LED/84618.aspx (725 words)

	Quantum Mechanics and its Paradox
		He intended to prove that nature cannot be explained in a rational way but requires the probabilistic interpretation of quantum mechanics because he claims the impossibility of giving a realistic interpretation to the experiment.
		Since, in practice, the quantum efficiency is smaller than 100%, some counts are missing on one of the detectors, therefore changing the number of pairs.
		In the case of an imperfect quantum efficiency of the detectors, when one of the detectors has not detected the particle, it is not possible for the operator to choose a new switch setting, since he does not know whether or not an event took place.
	www.newtonphysics.on.ca /Uncertainty/Uncertainty.html (2810 words)

	Uncertainties in Absolute Quantum Efficiency
		It is useful to distinguish at the outset errors arising from the limited precision with which the parameters of the adopted model are constrained by the available data, on the one hand, from those arising from inadequacies in the quantum efficiency model, on the other hand.
		Thus we shall sometimes use the phrase ``measurement errors'' as an abbreviation for ``errors in predicted quantum efficiency resulting from errors in measurement.'' We label the latter error type ``modelling errors,'' intending an analogous ellipsis.
		For many purposes it is therefore much more useful to conceive of the quantum efficiency vs. energy function itself, rather than the quantum efficiency at any particular energy, to be the random variable whose value is constrained by the model fitting.
	www.astro.psu.edu /xray/docs/cal_report/node125.html (338 words)

	NIST Quantum Information Networks Overview (Site not responding. Last check: 2007-11-03)
		The telescopes for the quantum channel are being assembled at the lower left.
		Classical and quantum physical link layers have been fully integrated and we have observed the generation of sifted quantum key at rates in excess of 3.5 Mbps over the 730 m free-space link.
		We still anticipate that with appropriate anti-reflection coatings and with reduced fiber loss the quantum efficiency may be pushed to at least 95%.
	math.nist.gov /quantum/overview.html (2350 words)

	Quantum Information Science
		Quantum mechanics is usually taught at the undergraduate and graduate levels as part of the standard physics and chemistry curriculum, but the emphasis is more on applications than on developing a solid comprehension of the subject’s strange and seductive foundations.
		In quantum teleportation, Alice receives a qubit in an unknown state, and destroys it by performing a Bell measurement on that qubit and a member of an entangled pair of qubits that she shares with Bob.
		For example, new quantum error correction protocols have been developed that are adapted to the dominant decoherence mechanism in ion trap and cavity QED computers, including a protocol that protects against certain types of dissipative events to all orders in the error probability.
	www.nsf.gov /pubs/2000/nsf00101/nsf00101.htm (13848 words)

	Method of monitoring changes in the detective quantum efficiency of an x-ray detector - Patent 6521886
		The detective quantum efficiency (DQE) is recognized as one of the important objective measures of the performance of an x-ray imaging detector.
		DQE is the measure of the ability of the detector to transfer signal-to-noise ratio from its input to its output.
		The DQE is a measure of the ability of the x-ray detector to transfer signal-to-noise ratio from its input to its output.
	www.freepatentsonline.com /6521886.html (2700 words)

	Quantum Efficiency
		The quantum efficiency (Q.E.) of a sensor describes its response to different wavelengths of light (see chart).
		Standard front-illuminated sensors, for example, are more sensitive to green, red, and infrared wavelengths (in the 500 to 800 nm range) than they are to blue wavelengths (400 - 500 nm).
		The different response to wavelengths also accounts for the fact that unfiltered CCD exposures of spiral galaxies will typically suppress star-formation regions (blue light) in the arms, and accentuate emission nebulae and dust lanes (red and infrared light).
	www.ccd.com /ccd101.html (268 words)

	IAAT (Astronomy): ORFEUS - The Echelle Spectrometer
		This graphics shows the efficiencies of the individual optical components of the Echelle spectrometer and the resulting total efficiency of the whole instrument.
		The efficiencies of the individual components are given in percent (left axis), while the efficiency of the whole instrument is given as effective area in cm
		The values given are the pure quantum effiency values without electronical losses due to selection or dead time effects.
	astro.uni-tuebingen.de /groups/orfeus/echelle.shtml (890 words)

	Encyclopedia of Laser Physics and Technology - quantum efficiency, laser gain medium, photodiode
		In a laser, the pump process may require the transfer of laser-active ions from one electronic levels (into which the ions are pumped) to the upper-state level of the laser transition.
		The quantum efficiency of this process is then the fraction of the absorbed pump photons which contributes to population of the upper laser level.
		In a photodiode, the quantum efficiency can be defined as the fraction of incident (or alternatively, of absorbed) photons which contribute to the external photocurrent.
	www.rp-photonics.com /quantum_efficiency.html (242 words)

	High-Quantum-Efficiency Photocathode for Photomultiplier Tubes
		Now Hamamatsu scientists have incorporated III-V semiconductor photocathodes of GaAsP(Cs) and GaAs(Cs) offering high quantum efficiency and low dark noise for applications requiring the detection of very weak light signals with high signal-to-noise ratios.
		Conventional PMTs typically have quantum efficiencies (the ratio of detected electrons to incident photons expressed as a percentage) in the vicinity of 20 percent in the visible light range to a few percent in the red and near-infrared.
		Photomultiplier tubes employing these cathodes have quantum efficiencies in the visible of up to 50 percent and over 15 percent in the near infrared.
	www.nasatech.com /Briefs/Sept99/PTB09991.html (732 words)

	Particle detection efficiency estimations (Site not responding. Last check: 2007-11-03)
		As shown in chapter 3.1, the particle detection efficiency depends on a number of factors, such as gas refraction index, its transparency, mirror reflection efficiency, PMT quantum efficiency and mirror optics.
		Open circles and open triangles represent the minimum and maximum quantum efficiencies of a group of seven PMTs tested at Jefferson Laboratory.
		used in the particle detection efficiency calculations was reduced from previous estimations for Freon-12 gas and was set at
	www.jlab.org /~vlassov/cc/node17.html (181 words)

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