We study the intrinsic noise in n-type Si crystals operating under high-frequency periodic electric fields. To simulate the dynamics of electrons in the bulk, by taking into account the main details of band structure, scattering processes, as well as heating effects, a Monte Carlo approach is used. The noise properties are investigated by computing the velocity fluctuations correlation function, its spectral density, and the total noise power for different values of the amplitude and frequency of the driving field. We show that the noise features are significantly affected by the electric field amplitude and frequency and discuss their peculiarities in comparison with those exhibited in the static field case. We find the integrated spectral density, i. e. the total noise power, monotonically reducing its value with the increase of the field frequency, for each amplitude of the applied field. These results can be considered a first step towards a full understanding of the physical characteristics of electronic noise in Si devices, driven by periodic electric fields, relevant, for example, for harmonic generation purposes.

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Recently, electrical injection of spin polarization in n-type and p-type silicon up to room-temperature has been experimentally carried out. Despite of these promising experimental results, a comprehensive theoretical framework concerning the influence of transport conditions on the spin depolarization process in silicon structures, in a wide range of values of temperature, doping concentration and amplitude of external fields, is still in a developing stage. In this contribution we use a semiclassical multiparticle Monte Carlo approach to simulate the electron transport and spin dynamics in lightly doped n-type Si crystals and numerically calculate the spin lifetimes of drifting electrons. Spin flipping is taken into account through the Elliot-Yafet mechanism, which is dominant in group IV materials. We discuss the influence of different intravalley and intervalley phonon interactions in the spin relaxation process during the spin transport. Our findings are in good agreement with those obtained by using different theoretical approaches. Moreover, our Monte Carlo predictions, in ranges of temperature and field amplitude yet unexplored, can guide future experimental studies towards a more effective design of room-temperature silicon based spintronic-devices.

The chapters cover a wide range of countries and sectors. National case studies on Argentina, Turkey, Italy, the United States, Mexico, the United Kingdom, China, South Africa, and India are organized in three thematic parts: transport and logistics; education, call centres, cleaners, platform work, and gamers; manufacturing and mining. The contributions on Argentina, by Dario Bursztyn, and on China, by Jenny Chan, have a strong historical character, covering respectively two centuries and four decades. Anna Curcio's chapter on Italian logistics workers offers very relevant insights into the dynamics of gender, migration, status, and race. Those interested in conducting a workers' inquiry themselves will be particularly attracted to the contributions on the United States, by Robert Ovetz, and on the United Kingdom, by the Notes From Below Project, for tested-on-the-ground models to replicate. Meanwhile, the chapter on India, by Lorenza Monaco, offers the most exhaustive reflections on experiences of conducting militant co-research.Overall, the book is a welcome contribution for labour activists and for global labour historians, social historians, and sociologists of labour, either Marxists or non-Marxists. Although trade union power has been declining for years already, with traditional class thinking being relegated ever since, scholars worldwide are still far from agreeing on how to conceptually and theoretically approach the wide variety of recent workers' struggles. This book helps in this search by challenging dominant academic approaches and assumptions, offering critique that calls for a response from scholars. There is no doubt, however, that for the book to successfully help to map the next terrain of class struggle at the global level, two more steps are required. First, it is paramount that workers' inquiries become more common, and this depends on whether this research call is heeded. Second, an overarching analysis of the insights from the case studies is required, something that is not included in the present volume. For now, this edited volume contains a rich collection of new research on an urgent topic, from the perspective of workers worldwide.