We introduce a kinetic theory of electron transport on the nanoscale, formulated in terms of the Fock space of an open many-electron system, and the “second quantization” Hamiltonian. To model a thermal electron reservoir (e.g., a metal electrode), the Fermi–Dirac distribution is derived from the corresponding density operator. A nanoscale system, weakly coupled to the reservoir, is modeled as an impurity. When the Born–Markov and secular approximations are valid, quantum master equations are derived, showing that the impurity equilibrates with the reservoir. To account for charge transport through the impurity, as in atomic point contacts or single molecule junctions, the master equations are generalized for cases of an impurity coupled to different reservoirs at different chemical potentials/temperatures. In these cases, we show that the system reaches a nonequilibrium steady state, where current flows through the impurity. Analytic expressions are derived for this steady state in simple models.

Chapter 5 uses concepts of diffusion and nucleation to understand phase transformations in ways beyond a simple usage of equilibrium phase diagrams. A number of nonequilibrium phenomena are described, which show how to understand some phase transformations that have impediments from nucleation and diffusion. In general, the slowest processes are first to cause deviations from states of equilibrium. For faster heating or cooling, however, sometimes the slowest processes are fully suppressed, and the next-slowest processes become important. Nonequilibrium processes in alloy freezing are explained, as is the glass transition. Approximately, Chapter 5 progresses from slower to faster kinetic processes. However, the last section discusses why kinetic processes based on activated state rate theory should bring materials to thermodynamic equilibrium.