Modern Car Handbook

The handbook presents innovative technologies of a modern car. Cars with internal combustion engines are mainly overviewed. Hybrid and electric vehicles are presented as well. Great attention is paid to technologies that ensure fuel economy and reduction of gas emissions. The newest internal combustion engine technology is presented and explained. The car passengers and driver safety systems are widely considered. The assist and self-adaptive technology principles for safely ride are reviewed and discussed too. Also, an introduction in the latest technologies that help to protect the surrounding road users and particularly pedestrians is delivered. Car security issues and some recommendations to protect your car from theft are introduced. Car computers elements and its applications for car control and diagnosis are examined. Widely and in details are discussed sensor system which applies in a modern car. Sensors operation principles (physics) and technologies are studied and presented as well.Experimental Version. Non-profit editio

Peculiarities of excitonic photoluminescence in Si δ-Doped GaAs structures

We present investigation of photoluminescence properties of Si δ-doped GaAs structures at different temperatures and various laser excitation intensities. Strong excitonic emission was observed in the δ-doped structures. The photoluminescence in the infrared region, below excitonic emission, originates from a non-phonon free electron-acceptor e-A transitions and longitudinal optical phonon sidebands of e-A transitions. Possible mechanisms for recombination of photocarriers are discussed, with a particular focus on an enhanced excitonic photoluminescence emission in comparison with that from intrinsic GaAs layers of the same structures

Excitonic light emission decay time measurements in moderately δ-doped GaAs/AlAs multiple quantum wells

The radiative recombination rate of moderately doped n-type and p-type GaAs/AlAs multiple quantum wells using a timecorrelated single photon counting system is presented. The experimental study has been obtained within a wide temperature range from liquid helium to room temperature and the work has focused on identifying photoluminescence decay rates based on freeexciton recombinations. It was found that the free exciton decay time was reduced in doped multiple GaAs/AlAs quantum wells, and that the reduction rate depends on both the concentration and doping type

Impurity-induced Huang-Rhys factor in beryllium delta-doped GaAs/AlAs multiple quantum wells fractional-dimensional space approach

This paper reports the observation of phonon sidebands in the photoluminescence spectra of Be acceptor-doped GaAs/AlAs multiple quantum wells. The intensity and energetic positions of the sideband lines are investigated experimentally for several quantum wells having various doping concentrations and photoluminescence excitation intensities. Theoretical analysis of a sideband-related lineshape, considering their energy position and impurity-induced spectra, has shown that phonon satellites can be attributed to free-electron -Be acceptor transitions involving longitudinal optical phonons of the GaAs-the host material of the studied quantum wells. The Huang-Rhys factor which determines the distribution of luminescence intensities between the phonon replicas and the main no-phonon peak was examined both experimentally and theoretically by varying the quantum well width. Thus, it has been found that this factor increases monotonically from 0.052 to 0.11 as the width of the quantum well decreases from 20 nm to 5 nm. The dependence of the Huang-Rhys factor on the width of the quantum well for a free-to-acceptor recombination was calculated applying the fractional-dimensional space approach. The proposed model adequately describes the experimentally determined dependence of the Huang-Rhys factor

Radiative recombination spectra, of heavily p-type δ-doped GaAs/AlAs MQWs

We present a study of the photoluminescence properties of heavily Be δ-doped GaAs/AlAs multiple quantum wells measured at room and liquid nitrogen temperatures. Possible mechanisms for photocarriers recombination are discussed, with a particular focus on the peculiarities of the excitonic and free carriers-acceptors photoluminescence emissions occurring below and above the Mott metal-insulator transition. Moreover, based on a simple theoretical model, it is found that the critical impurities concentration to observe the Mott transition in the multiple quantum wells samples exhibiting 15 nm wells width and 5 nm thick barrier layers is ≈3 × 1012 cm-2

Radiative Recombination Spectra of Heavily p-Typeδ-Doped GaAs/AlAs MQWs

We present a study of the photoluminescence properties of heavily Be δ-doped GaAs/AlAs multiple quantum wells measured at room and liquid nitrogen temperatures. Possible mechanisms for photocarriers recombination are discussed, with a particular focus on the peculiarities of the excitonic and free carriers-acceptors photoluminescence emissions occurring below and above the Mott metal-insulator transition. Moreover, based on a simple theoretical model, it is found that the critical impurities concentration to observe the Mott transition in the multiple quantum wells samples exhibiting 15 nm wells width and 5 nm thick barrier layers is ≈3 × 1012 cm-2

Enhancement of the excitonic photoluminescence in n+/i-GaAs by controlling the thickness and impurity concentration of the n+ layer

This communication presents the photoluminescence spectra of molecular beam epitaxially grown GaAs structures made from a 500 nm thick layer of intrinsic conductivity capped with a silicon doped layer with a film thickness ranging from 10 to 100 nm. Two different doping concentrations of the cap layer, NSi = 1017 cm-3 and NSi = 1018 cm-3, was considered. The results showed the excitonic line of i-GaAs layer enhancement. The intensity of excitonic line was about 160 times higher for the homojunction compared to the intrinsic conductivity epitaxial layer at liquid helium temperature. Possible mechanisms of the observed intensity enhancement in the n+/i-GaAs homojunction are discusse