scholarly journals Power-Law Blinking Quantum Dots: Stochastic and Physical Models

2005 ◽  
pp. 327-356 ◽  
Author(s):  
Gennady Margolin ◽  
Vladimir Protasenko ◽  
Masaru Kuno ◽  
Eli Barkai
Keyword(s):  
Quantum Dots ◽  
Power Law ◽  
Physical Models

Nonexponential “blinking” kinetics of single CdSe quantum dots: A universal power law behavior

2000 ◽  
Vol 112 (7) ◽  
pp. 3117-3120 ◽  
Author(s):  
M. Kuno ◽  
D. P. Fromm ◽  
H. F. Hamann ◽  
A. Gallagher ◽  
D. J. Nesbitt
Keyword(s):  
Quantum Dots ◽  
Power Law ◽  
Cdse Quantum Dots ◽  
Universal Power Law ◽  
Kinetics Of

An Intermittent Generation–Recombination Process as a Possible Origin of 1/f Fluctuations in Semiconductor Materials

2017 ◽  
Vol 16 (04) ◽  
pp. 1750034 ◽  
Author(s):  
Ferdinand Grüneis
Keyword(s):  
Quantum Dots ◽  
Temperature Dependence ◽  
Power Law ◽  
Phonon Scattering ◽  
Recombination Process ◽  
Semiconductor Materials ◽  
Conduction Electrons ◽  
Fluorescence Intermittency ◽  
The Impact ◽  
Electron Phonon Scattering

Inspired by the phenomenon of fluorescence intermittency in quantum dots and other materials, we introduce small off-states (intermissions) which interrupt the generation and recombination (= [Formula: see text]–[Formula: see text]) process in a semiconductor material. If the remaining on-states are power-law distributed, we find an almost pure 1/[Formula: see text] spectrum. Besides well-known [Formula: see text]–[Formula: see text] noise, we obtain two 1/[Formula: see text] noise components which can be attributed to the intermittent generation and recombination process. These components can be given the form of Hooge's relation with a Hooge coefficient [Formula: see text] describing the contribution of the generation and recombination process, respectively. Herein, the coefficients [Formula: see text] and [Formula: see text] describe impact of intermissions which in general are different for the generation and recombination process. The impact of [Formula: see text]–[Formula: see text] noise on 1/[Formula: see text] noise is comprised in the coefficient [Formula: see text] for the generation and [Formula: see text] for the recombination process. These coefficients are specified for an intrinsic and a slightly extrinsic semiconductor as well as for a semiconductor with traps; for the latter, the temperature dependence of 1/[Formula: see text] noise is also investigated. 1/[Formula: see text] noise is shown to be inversely related to the number of neutral and ionized [Formula: see text]-atoms rather than to the number of conduction electrons as defined in Hooge's relation. As a possible origin of 1/[Formula: see text] noise in semiconductors, electron–phonon scattering is suggested.

Power-law photoluminescence decay in quantum dots

2014 ◽  
Author(s):  
Karel Král ◽  
Miroslav Menšík
Keyword(s):  
Quantum Dots ◽  
Power Law ◽  
Photoluminescence Decay

scholarly journals Power-law dependence of the angular momentum transition fields in few-electron quantum dots

2004 ◽  
Vol 69 (7) ◽  
Author(s):  
E. Anisimovas ◽  
A. Matulis ◽  
M. B. Tavernier ◽  
F. M. Peeters
Keyword(s):  
Quantum Dots ◽  
Angular Momentum ◽  
Power Law ◽  
Electron Quantum

Experimental study on the effects of fractures on elastic wave propagation in synthetic layered rocks

Geophysics ◽  
2016 ◽  
Vol 81 (4) ◽  
pp. D441-D451 ◽  
Author(s):  
Tianyang Li ◽  
Ruihe Wang ◽  
Zizhen Wang ◽  
Yuzhong Wang
Keyword(s):  
Wave Propagation ◽  
Fractal Dimension ◽  
Power Spectrum ◽  
Elastic Wave ◽  
Power Law ◽  
Layered Media ◽  
Physical Models ◽  
P Wave ◽  
Fracture Density ◽  
S Wave

Fractures greatly increase the difficulty of oil and gas exploration and development in reservoirs consisting of interlayered carbonates and shales and increase the uncertainty of highly efficient development. The presence of fractures or layered media is also widely known to affect the elastic properties of rocks. The combined effects of fractures and layered media are still unknown. We have investigated the effects of fracture structure on wave propagation in interlayered carbonate and shale rocks using physical models based on wave theory and the similarity principle. We have designed and built two sets of layered physical models with randomly embedded predesigned vertically aligned fractures according to the control variate principle. We have measured the P- and S-wave velocities and attenuation and analyzed the effects of fracture porosity and aspect ratio (AR) on velocity, attenuation, and power spectral dimension of the P- and S-waves. The experimental results indicated that under conditions of low porosity ([Formula: see text]), Han’s empirical velocity-porosity relations and Wang’s attenuation-porosity relation combined with Wyllie’s time-average model are a good prediction for layered physical models with randomly embedded fractures. When the porosity is constant, the effect of different ARs on elastic wave properties can be described by a power law function. We have calculated the power spectrum fractal dimension [Formula: see text] of the transmitted signal in the frequency domain, which can supplement the S-wave splitting method for estimating the degree of anisotropy. The simple power law relation between the power spectrum fractal dimension of the P-waveform and fracture density suggests the possible use of P-waves for discriminating fracture density. The high precision and low error of this processing method give new ideas for rock anisotropy evaluation and fracture density prediction when only P-wave data are available.

The Fluorescence Intermittency for Quantum Dots Is Not Power-Law Distributed: A Luminescence Intensity Resolved Approach

ACS Nano ◽  
2014 ◽  
Vol 8 (4) ◽  
pp. 3506-3521 ◽  
Author(s):  
Robert Schmidt ◽  
Cornelius Krasselt ◽  
Clemens Göhler ◽  
Christian von Borczyskowski
Keyword(s):  
Quantum Dots ◽  
Power Law ◽  
Luminescence Intensity ◽  
Fluorescence Intermittency

scholarly journals Spectro-timing analysis of MAXI J1535–571 using AstroSat

2019 ◽  
Vol 488 (1) ◽  
pp. 720-727 ◽  
Author(s):  
Yash Bhargava ◽  
Tomaso Belloni ◽  
Dipankar Bhattacharya ◽  
Ranjeev Misra
Keyword(s):  
Black Hole ◽  
Power Law ◽  
Intermediate State ◽  
Timing Analysis ◽  
Physical Models ◽  
Periodic Oscillations ◽  
Black Hole Candidate ◽  
Centroid Frequency ◽  
Spacecraft Orbits ◽  
Tight Correlation

Abstract We report the results of the analysis of an AstroSat observation of the black hole candidate MAXI J1535–571 during its hard-intermediate state. We studied the evolution of the spectral and timing parameters of the source during the observation. The observation covered a period of ∼5 d and consisted of 66 continuous segments, corresponding to individual spacecraft orbits. Each segment was analysed independently. The source count rate increased roughly linearly by ∼30 per cent. We modelled the spectra as a combination of radiation from a thermal disc component and a power law. The timing analysis revealed the presence of strong quasi-periodic oscillations with centroid frequency νQPO fluctuating in the range of 1.7–3.0 Hz. We found a tight correlation between the QPO centroid frequency νQPO and the power-law spectral index Γ, while νQPO appeared not to be correlated with the linearly increasing flux itself. We discuss the implications of these results on physical models of accretion.

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