Applications and Metrology at Nanometer-Scale 2. Abdelkhalak El Hami
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is the scale fitting the domain to which corresponds the age of the Universe deduced from observations related to the Big Bang based on the inflationary model in an expanding Universe.
After the Big Bang, the elementary subatomic particles had no mass and could travel at the speed of light. After the expansion of the Universe and its cooling, the particles interacted with the Higgs field and consequently gained a mass.
In the history of the Universe, the elementary particles interacted with the Higgs field, 10–12 s after the Big Bang. The value of 125 GeV is considered as the critical value between a stable universe and a metastable universe. The “standard model of cosmology” elaborated at the beginning of this century, towards 2000, is probably at present the best model that enables the description of the evolution of the Universe, the significant stages in the history of the observable Universe as well as its current content, as revealed by astronomical observations. The standard model describes the Universe as an expanding homogeneous and isotropic space, on which large structures are overlaid as a result of the gravitational collapse of primordial inhomogeneities, which were formed during the inflation phase. There are still questions to be addressed, such as the nature of certain constituents of the Universe, black matter, and black energy and their relative abundance.
The inflationary model relies on the hypothesis of the Universe expanding with an exponential acceleration R(t)=R0exp(H(t)t), 10–30 s after the Big Bang, where H(t) is the Hubble constant. This constant is measured from the Doppler effect, which explains the red shift of the light radiation emitted by a distant star that is receding from the point of observation. The inflationary model allows for a plausible interpretation of the CMB isotropy, with relative variations of the measured temperature of 10–5. Based on the data provided by the Hubble, COBE (Cosmic Background Explorer) and WMAP (Wilkinson Microwave Anisotropy Probe) telescopes, as well as by the BOOMerang (Balloon Observations Of Millimetric Extragalactic Radiation ANd Geophysics) and MAXIMA (Millimeter Anisotropy eXperiment IMaging Array) experiments, scientists were able to determine the age of the Universe is 13.75 billion light-years.
The Universe is presently in accelerated expansion: if its speed is 70 km/s at 1 Megaparsec, it doubles at 2 Megaparsec, reaching 140 km/s and so on. Considering the Doppler shift or the red shift for the receding stars, and therefore the fact that not only are the stars receding, but also those that are twice farther recede twice faster, therefore considering the metrics applicable to the space that is stretching while galaxies are receding, the 13.8 billion years between the beginning of the rapid expansion of the Universe 10–30 s after the Big Bang amount to 46.5 billion light-years, which is a radius of 93 billion light-years. Obviously, the light of stars that are at the periphery or at the cosmological horizon can no longer reach us, but as what we observe today goes back to the time needed for light to reach us while traveling a distance in a stretching space.
These two examples show that at each dimensional scale, besides the appropriate experimental measurement techniques required for observation, we must have a good mastery of the theories adapted for the interpretation and analysis of the gathered data. At each scale, the engineer must acquire specific knowledge elaborated in the laboratories and develop the competences to enable the mastery of technologies and the implementation of innovations.
This book which provides applications for Volume 2 of the Reliability of Multiphysical Systems Set (Nanometer-scale Defect Detection Using Polarized Light), focuses on knowledge elaborated at the nanometer scale for applications in the field of engineering sciences. The subjects approached are related to simulation experiments and engineering of nanometer-scale systems. The light–matter interaction has a special place among the subjects addressed, because the analysis of the properties and characteristics of matter is most often possible due to light being used as a probe. Similarly, simulation according to theoretical models based on quantum mechanics principles requiring field theory is also given particular attention.
Nanotechnologies and nanosciences are identified as sources of breakthrough innovations that will lead to the development of technologies that are considered primordial in the 21st Century. They should be deployed in eco-innovations and will increasingly become pervasive in the societal applications in various sectors. Without pretending to provide an exhaustive list, several examples are worth being mentioned: new energies and their recovery and storage, water purification, new materials that are lighter and more resilient for land and space transportation, construction and buildings, information technologies with quantum computers, embedded electronic systems and factory 4.0. The trend according to which states throughout the world offer financial support for the development of long-term projects in this field dates back to the beginning of the 21st Century. This is a reflection of the economic growth potential in nanotechnologies.
Similar to the inflationary model proposed by cosmologists to explain the countless galaxies and planetary systems, suns and black holes that constitute them, there was also a sharp increase in the volume of activities in nanosciences. The subjects approached in this book and in Volume 2 of the Reliability of Multiphysical Systems Set (Nanometer-scale Defect Detection Using Polarized Light) concern the field of engineers working in mechatronics, robotics and computation in modeling and simulation, for the societal spin-offs of nanotechnologies in the fields of land and space transportation, handicap, information and simulation technologies in a systemic approach. The level of knowledge acquired by the engineer should make innovation in nanotechnologies possible.
The contents of Nanometer-scale Defect Detection Using Polarized Light and Applications and Metrology at Nanometer Scale 1 & 2, jointly written by three authors, aim to develop knowledge that is essential at the nanometer scale, enabling trainee-engineers or engineers to develop nanotechnology-based devices or systems. To promote the deployment of nanotechnologies, the authors of these three books whose joint competences and experiences associate know-how in fundamental physics, engineering sciences and industrial activities cover a wide spectrum of application domains. Nanometer-scale Defect Detection Using Polarized Light builds a theoretical and experimental basis for understanding nanometer-scale metrology. This book in two volumes, Applications and Metrology at Nanometer Scale, enriches this theoretical basis with applications in the form of corrected exercises.
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