QUANTUM EFFICIENCY

of great interest because it would be highly reproducible, inexpensive, minimally toxic and capable of forming products that are easily dissolved in water. Close control of the optical and structural properties of MSNs (for example, CdSe) that are synthesized directly in a colloidal aqueous solution[r]

allows one to obtain information on the reflecting properties of the photoactive surface. This information is particularly interesting for the evaluation of the photoconversion internal quantum efficiency. Moreover, when the photovoltaic device under study has a photon transparent supp[r]

the spectral optical properties and the intrinsic internal quantum efficiency behaviour, one can estimate absolute external quantum efficiency at any photon energy when there is no carrier recombination. Probability of surface recombination is typically dominant and becom[r]

Geiger Avalanche Photodiodes (G-APDs) and Their Characterization 261 Different configurations have been investigated and some other measurements were carried out with the same results. 9. PDE measurements Only a fraction of the photons impinging on the sensor will actually trigger an avalanche to p[r]

built-in electric field, cau sing a remarkable quantum-confined stark effect [QCSE] which reduces the interna lquantum efficiency [IQE] of the QDs. The reason is thatthe built-in electric field leads to energy ban d declineand separation of electron and hole wave functions,resulting in[r]

wavelength. For T, angular and polarization dependence can also be calculated. Therefore, ηext can be estimated by assuming simplified η'int dependence or by using independent experimental results of η'int. 3.2 Intrinsic quantum efficiency The ideal internal quantum efficienc[r]

2+reveals green luminescenc ein CeF3:Mn and orange luminescence in CePO4:Mn,resulting from the crystal field differences of these twohosts.WeworkedoutthatthehighestMn2+lumines-cence quantum efficiency can reach 14% and 0.6% inthe CeF3:Mn and CePO4NCs, respectively. Our resultsmay find[r]

leaf photosynthetic performance. Little black points, which correspond to PSII maximum efficiency (Fv/Fm) values close to zero, characterize the mcd1 leaves. Similarly, the light adapted quantum efficiency (ΦPSII) values show a homogeneous distribution over wild type leaf lamina[r]

magnetic field (Pavlovich & Epshtein, 1977), the expressions for the nonlinear absorption coefficient has the sum over the quantum number of confined electron-confined optical phonon and contain the cyclotron frequency. All expressions for the nonlinear absorption coefficient turn bac[r]

of oneorder-of-magnitude discrepancy.11Modern devices often consist of multi-compound semiconductors of unknown thermalproperties. In such cases, one has to rely on approximate expressions determining particularparameter upon parameters of constituent materials (see for example Nakwaski (1988)).8.5[r]

calibration. If we want to query the role and status of thermodynamics in quantum chemistry, it is necessary to consider the practices of research from which they originate, i.e., the techno-scientific closure which combines quantum mechanics, approximations, instrumental and algorithm[r]

lengths. Materials that have high absorption coefficientsover the whole spectral region from NIR to UV are neededfor high power conversi on efficiency. During the las t f ewyears, instead of organic dyes, the narrow band gap semi-conductor quantum dots (QDs) such as CdS [6,7], CdSe[7-9[r]

NANO EXPRESS Open AccessElectron cotunneling through doubly occupiedquantum dots: effect of spin configurationJian Lan, Weidong Sheng*AbstractA microscopic theory is presented for electron cotunneling through doubly occupied quantum dots in theCoulomb blockade regime. Beyond the semiclassic f[r]

This equation is obtained by standard separation methods—decomposing the wave func-tion into a radial and an angular part—as they are taught in every first course on quantummechanics, see for instance [5]. For a more analytic approach to the subject, see for in-stance [4]. We briefly describe the moti[r]

[22-23]. According to this theory, electrons with opposite momenta and antiparallel spins form pairs when their attraction, due to the electron and phonon interaction in these materials, overcomes the Coulomb repulsion between them. The so-called Cooper pairs are condensed to a minimum energy state,[r]

Thoery* atoms and molecules have unique spectra.* resonance – resonance frequency+ A plot of amplitude vs. excitation frequency willhave a peak centered at the resonancefrequency* In quantum mechanical systems, the analogousresonance is a coupling of two quantummechanical stationary states of[r]

detail.The amount of information being transmitted and processed is a fundamental resource in quantum communication and computation. A highdimensional entangled state can transmit more information than conventional two-dimensional systems. This reduces the noise threshold limitingthe security[r]

Fig. 11. Visible light sensitivity: The I-V curve shows response to visible light (white LED). It is important to note that each experiment included control detectors consisting of silicon pieces treated the same way as the detectors but without being loaded with quantum dots. None of the con[r]

2(M) the subspace ofmean zero functions.Theorem 1.4 provides a sharp answer to the general question of when acombination of fast unitary evolution and dissipation produces a significantlystronger dissipative effect than dissipation alone. It can be useful in any model648 P. CONSTANTIN, A. KISELEV, L.[r]

‘‘blue shift’’ of extremely narrow luminescence peaks ofisolated dots [1–3]. Confinement effects in magneto-capacitance and infrared absorption have also beenobserved experimentally [4, 5].Physical properties of so-called ‘‘quantum lenses,’’ orlenticular QDs are of special interest [4, 6, 7].[r]